questions2_(1300 results).txt

algorithm					Facebook Senior Engineer On-site 2017  1st Round Question 1: Binary tree to doubly linked list. Question 2: Read 4 (Given the read4 API, read an entire file)  2nd Round Culture fit. No coding.  3rd Round Question: System Design POI (Point of Interest. Given a point, find things within a radius).  Lunch 4th Round Question 1: Decode way Question 2: Random max index  5th Round Question: System design + component-wise design on download manager

algorithm					5th Round Open-ended question What happens when you type a url in the browser and hit enter?  Second question Given an array of integers, print all the numbers that meet the following requirement - when the number is greater than every number on its left and smaller than every number on the right.

algorithm					You are given an array of integers both negative and positive. Print the maximum continuous sum of the array and if all the elements are negative, print the smallest of them. Ex : [-20, -5, -2, -9] :> -2(-2) Ex : [20, -19, 6, 9, 4] :-> 20(20) Ex : [10, -3, 4, -2, -1, 10] -> 18 (10, -3, 4, -2, -1, 10)  Thanks velu007 for pointing out the mistake

algorithm					Given some email ids, and a similarity function which says whether two email ids are similar, determine all the sets of email ids that are similar to each other.

algorithm					Given a list of URLs entered by a user write a program to print unique and most recently used URLs. For example if user entered the following: - 1. google.com 2. yahoo.com 3. wsj.com 4. google.com  The output should be :- 1. google.com 2. wsj.com 3.yahoo.com

algorithm					Given a sorted array, find all the numbers that occur more than n/4 times.

algorithm					In school a student gets rewarded if he has an attendance record without being absent for more than once or being late for 3 times continuously.  Given a student's attendance record represented by a string with 3 possible characters 'L'(Late), 'A'(Absent), 'O' (On time),  check whether the student qualifies for the reward.   e.g.  @INPUT (String) "OLLAOOOLLO"  @RETURN (Boolean) False  The student does not qualify for reward because "LLA" means he was late for 3 times in a row.   @INPUT (String) "OLLOAOLLO"  @RETURN (Boolean) True     Follow-up:  If known the length of the attendance string is n, how many possible ways there is to attend school and make sure you get the reward.

algorithm					Given an array it can be of 4 types (a) Ascending (b) Descending (c) Ascending Rotated (d) Descending Rotated  Find out which kind of array it is

algorithm					The following code has a bug, find it and fix it

algorithm					Write a function that receives a string an returns a list of all the substrings (of length >= 2) composed by consecutive characters. E.g input : "BCCDE" , output: ["BC","CD","CDE","DE"]

algorithm					/**  * Given a nested list of integers, returns the sum of all integers in the list weighted by their REVERSED depth.  * For example, given the list {{1,1},2,{1,1}} the deepest level is 2. Thus the function should return 8 (four 1's with weight 1, one 2 with weight 2)  * Given the list {1,{4,{6}}} the function should return 17 (one 1 with weight 3, one 4 with weight 2, and one 6 with weight 1)

algorithm					Early on I prefer to post the interview questions with a simplified description or only present the algorithmic part of it. Because it's hard for our students to memorize the full description of a problem. Therefore often times only the algorithm behind the question is given.  But somehow a user of this site @concernedCoder gets unhappy with it. So from today on, we will try to recover the original version of the question as much as possible.  We assure you all of the questions we posted are real  questions that you have a good chance to come across during a coding interview. Anyone who has experience in a coding interview should be able to see that.   Here is the full description of a recent Amazon OA question. The reason why we are able to provide the full description is because it's the online assessment. But for an on-site interview it's almost impossible to recover the questions perfectly.  Title: Item Recommendations Amazon wants to recommend items to a customer who has just made a purchase. Amazon's recommendation algorithm is based on item 'connection'. Two items are 'strongly connected' if a single customer bought both of them. Two items are 'weakly connected' if they are both strongly and weakly connected to some other third item.  Your  task is to determine the number of the items strongly and weakly connected to a given item.  You are provided the item id represented as a string, as well as the list of customer purchases represented as an array of strings. Each element in the array consists of a customer id(represented as a string) and an item id (also represented as a string). The two ids are separated by a colon. For example, if they element in the array is "ABJA:Z42G" then that means customer ABJA purchased item Z42G. Your output consists of an array, where the first element in the array represents the number of items strongly connected to the provided item id and the second element represents the number of items weakly connected to the provided item id. For example, if you were provided with the following input: determineRecommendation("ABC",["first:ABC", "first:HIJ", "sec:HIJ", "sec:KLM", "third:NOP", "fourth:ABC", "fourth:QRS", "first"DEF", "fifth:KLM", "fifth:TUV"])  You would return the following array: [3, 2] since ABC is strongly connected to 3 items: DEF, HIJ and QRS and is weakly connected to 2 items: KLM and TUV   Although the description is long, the problem is just asking for 'search (with either DFS or BFS) in a graph'.

algorithm					On google search, how to enable key word auto completion after a few letters typed.  Follow-up: How to rank the words if they are weighted by frequency?

algorithm					Find largest sub-array?

algorithm					You have two servers. Both of these servers have an identical file with billion characters except for one single character. These servers are connected over a very slow connection.   How do you find the different character?  My ans: split those files in to batches of characters of 10,000 (say), now calculate checksum and compare the checksums for the chunks of 10,000 character lines. So now you are just comparing 'ints' and not the files per say. (remember the connection is very slow)  His question: How do you optimize this?

algorithm					Given a set of possibly overlapping rectangles in different levels (All of which are "not rotated", can be uniformly represented as (left-bottom,right-top) tuplets), return a minimal set of (non-rotated) non-overlapping rectangles, that occupy the same area.   The rectangle at lower level has more priority than at higher levels.

algorithm					Write a function that receives a position in 2 dimensional (x,y) array, which was initially initialized with 'o' (signals "water"), the function changes the value/state of that position to 'x' (signals "land") and returns the number of isles in the board. For example, for 3x3 board, it will initially look like the following: o o o o o o o o o After calling the function with the position (1,2), the board will look like the following: o o x o o o o o o and the functions returns 1 An isle is defined as 'x' surrounded horizontally and vertically with 'o'    In the following board there is only one isle o o o o x x o x o

algorithm					I got my interview yesterday and the problem they asked me was: Giving a method intToEnglish that receives an int as a parameter, how do you return its representation in english words. The number can be of any size but no more than around 2 billion since the parameter is an int 232

algorithm					# There's a room with a TV and people are coming in and out to watch it. The TV is on only when there's at least a person in the room. # For each person that comes in, we record the start and end time. We want to know for how long the TV has been on. In other words: # Given a list of arrays of time intervals, write a function that calculates the total amount of time covered by the intervals. # For example:  # input = [(1,4), (2,3)] # > 3 # input = [(4,6), (1,2)] # > 3 # input = {{1,4}, {6,8}, {2,4}, {7,9}, {10, 15}} # > 11

algorithm					Find the median of an unsorted array. Have to do better than O(nlogn) time. e.g. Given [2, 6, 1] return 2 Given [2, 6, 1, 4] return 3 which is sum of the two elements in middle over 2

algorithm					Giving a string and an string dictionary, find the longest string in dictionary which can formed by deleting some characters of the giving string. eg:S = abpcplea, Dict = {ale, apple, monkey, plea}, the return "apple"  I was thinking of the following approach,  Build a Trie for all words in the Dict - O( n * k) where k is the longest string in the dict For each character c, in S check if there is a word in Trie that starts with it and has the letters that appear in S after c. We can short circuit based on remaining characters and the length of longest string found so far. This should take O( N * k) where N is length of S.

algorithm					/**  Given many coins of 3 different face values, print the combination sums of the coins up to 1000. Must be printed in order.   eg: coins(10, 15, 55)  print:  10  15  20  25  30  .  .  .  1000  */

algorithm					Find all comments in the Java (it could be Python or any other language of your choice) codes thats parsed in as a string.  You may assume the codes given is valid.  Input is a single string, e.g. String codes =     /*   file created by aonecode.com\\n  +      welcome to the tech blog*/      \\n  +     //main method\\n  +     public static void main(String[] args) { \\n  +      System.out.println(//welcome);    //output\\n  +     }   Output is a list of strings  List<String> ret =     [       file created by anecode.com\n      welcome to the tech blog,     main method,     output     ]

algorithm					Q: If you were given a series of equations e.g. [A = B, B = D, C = D, F = G, E = H, H = C] and then another series [A != C, D != H, ..., F != A ]  Check whether the equations combined is valid.  For the example given, your program should return 'invalid', because the first series implies that A = C, which contradicts the statement A != C in the second series.

algorithm					Calculate and replace repeated characters in a string with their number of occurrences.  Example :  aaaggbbbbc 3a2g4b1c

algorithm					Sort elements by frequency, print the elements of an array in the decreasing frequency if 2 numbers have same frequency then print the one which came first.

algorithm					Write a program which will bold the sub-string found in string (HTML Style).

algorithm					Write code to decode strings. For example, String str = "3[a2[bd]g4[ef]h]", the output should be "abdbdgefefefefhabdbdgefefefefhabdbdgefefefefh".  My solution is as follows.

algorithm					Print first pair of mis-matching leaves (first pair as in in-order) given two pre-order traversal arrays of BSTs.  e.g.

algorithm					Randomly select one of the weighted items from a  linked list. (you may only go through the list once)  e.g.  weight 1.6 -> weight 0.2-> ... -> weight 3.4 randomly select one item based on the weight. The higher the weight is, the more likely to be selected

algorithm					Given a list of system packages, some packages cannot be installed until the other packages are installed. Provide a valid sequence to install all of the packages.  e.g. a relies on b b relies on c  then a valid sequence is [c, b, a]

algorithm					Q: Find the absolute paths to all directories with image files, given a file system that looks like this. The subdirectory is one indent over.

algorithm					Q: List all comments in the given segment of codes. It's pretty tricky since there is a lot of things to be considered, especially the escape characters.

algorithm					Given two strings needle and haywards that contains ASCII characters,write an algorithm to output a list of 0-based indices of the occurances of all anagrams of needle in haystacks

algorithm					down vote favorite Consider the following series:  A := 1 B := A*2 + 2 C := B*2 + 3 and so on... Write a program that:  -outputs the number corresponding to a given letter;  -given a string of letters like 'GREP', computes the sum of the numbers corresponding to all the letters in the string (i.e., G + R + E + P), as given by the above series; and  -given a large number (that would fit into a standard 32-bit integer), finds the shortest string of letters corresponding to it. You may use a greedy approach for the last part. Compute the values of the numbers corresponding to letters as and when required and DO NOT pre-compute beforehand and store them in a data structure.

algorithm					An interesting question asked in Googles phone interview : suppose a row of parking lot with n spots, one of them is empty and n-1 spots are occupied with cars. Only one operation is allowed: move one car from its position to the empty spot. Given a initial order of cars and a final order, output steps needed to convert initial order to final oder with that operation.   Follow up: Minimize steps needed.  ex:  {1 2 3 -1 4 5} move car 1 to empty spot(denoted as -1) will make it {-1,2,3,1,4,5} push 1 to the output list because you move car 1 to the empty spot  suppose you have a initial order {1 2 3 -1 4 5} and a final order  {5,1,-1,3,2,4}, you need to transfer {1 2 3 -1 4 5} to {5,1,-1,3,2,4}, push each car moved into a output list.

algorithm					Given points on a plane like (0,0), (1,0), (0,1), (1,1), (0,2), (2,2), (1,2). How many rectangles can be formed ?

algorithm					Given a singly linked list: 1->2->3->4->5 Change it to 1->5->2->4->3 using O(1) space

algorithm					given a stream of natural numbers ,  and a array J contains integers in increasing orders operations performed J = [2,3,4] 1 2 3 4 5 6 7 8 9 10..27....100...1111 first operation  J[0] = 2 => remove every 2nd integer  now the stream is 1 3 5 7  27 J[1] = 3 remove every 3rd stream is now 1 3 7      3rd given a natural number n , find if it will survive given J, or at what index it will  die.

algorithm					Return the length of longest possible chunked palindrome string.  Examples :   Input : VOLVO  Output : 3 Explanation : (VO)L(VO)   Input : merchant  Output : 1  Explanation : No chunks possible.  Input :  ghiabcdefhelloadamhelloabcdefghi  Output : 7  Explanation :  (ghi)(abcdef)(hello)(adam)(hello)(abcdef)(ghi)

algorithm					Given a list of manager and employee information represented in hashMap entries {AAA->BBB,CCC,EEE},{CCC->DDD}. Print company structure tree with proper indentations. BBB, CCC and EEE directly reports to AAA, so they have one white space before "-", DDD reports to CCC, it has two whitespace before "-". The input is map<String,List<String>>

algorithm					A producer continuously produces a stream of characters. There are multiple consumer threads which read the chars and match to one of known strings and increment the counter for that pattern. Write the consumer function. Show how you will synchronize and maintain parallelism.  Ex: Producer: abcdegabccaabbaacv ...... Known strings[] = {"ab", "aa", "fff" ... } patternMatchCount[] = {3, 2, 0 ... }

algorithm					Given a dictionary and an char array print all the valid words that are possible using char from the array.  Ex- char[] arr = {'e','o','b', 'a','m','g', 'l'}  Dict - {"go","bat","me","eat","goal", "boy", "run"}  Print - go, me, goal.  We can pre-compute as much we want but the query time must be optimal.

algorithm					Given a pattern and a string - find if the string follows the same pattern Eg: Pattern : [a b b a], String : cat dog dog cat

algorithm					Given a binary tree and a target number, return whether or not there exist a path that can create target number. All inputs are integers. Target is not a string.  NOTE:: this is not path sums to target number ex: 3 4 5 6 7 8 9  359 = return true 38 = return false 47 = return true 6 = return true

algorithm					Tom works in a warehouse. A billion (1,000,000,000) boxes are arranged in a row. They are numbered from one to one billion (from left to right). Some boxes contain a basketball (at most one basketball in each box). In total, there are N basketballs.Tom wants to organize the warehouse. He would like to see all the basketballs arranged next to each other (they should occupy a consistent interval of boxes). In one move, Tom can take one basketball and move it into an empty box. What is the minimum number of moves needed to organize the basketballs in the warehouse?  Write a function:

algorithm					You are the main character in a game where you have to defeat a number of enemies in order. The player has a strength value and an initial amount of money. Each enemy also has a strength value, plus a price.  When facing each enemy you can either: 1) Fight him (if your strength is enough). You keep your money. 2) Bribe him (if you have the necessary money). You subtract the enemy's price from your money, and it joins you and adds its strength to yours.  Given a starting strength and amount of money, calculate the optimal strategy and the amount of money you end with (-1 if impossible).  This can be easily solved recursively in O(2^n) basically trying out each option at every enemy. But is there a polynomial solution, maybe involving DP?

algorithm					Finding biggest plus sign "+" in a sparse matrix(matrix with elements 0 and 1) For example, the biggest plus sign for following matrix is located at (2,2), with length 1 for each edge(Yes, each edge should have same length) 0 0 1 0 0 1 0 1 0 1 0 1 0 1 1 1 1 1 1 1 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0  Hint: use DFS/BFS

algorithm					Given a list of coin values, and quantity of each type of coin. Write a program to return the set of all possible sums which can be made using those coins. ex. coins = [10, 50, 100, 500] quantity = [5, 3, 2, 2] sum could be 400 , 300 ,200 , 100

algorithm					Given a function getRandom that returns a random double in [0,1). Write a function getRandomPermutation(int n) that takes a positive integer n as argument and returns a random permutation of first n natural numbers.

algorithm					Define amazing number as: its value is less than or equal to its index. Given a circular array, find the starting position, such that the total number of amazing numbers in the array is maximized. Example 1: 0, 1, 2, 3 Ouptut: 0. When starting point at position 0, all the elements in the array are equal to its index. So all the numbers are amazing number. Example 2: 1, 0 , 0 Output: 1. When starting point at position 1, the array becomes 0, 0, 1. All the elements are amazing number. If there are multiple positions, return the smallest one.  should get a solution with time complexity less than O(N^2)

algorithm					Given 'n' circles (each defined by center and radius)  Write an algorithm to detect if circles intersect with any other circle in the same plane  Better than O(n^2) complexity

algorithm					Given the village of a map represented as a 2D grid containing houses,bushes and open-spaces, write a program to find a point for conducting a meeting in the map. Such point should be minimum from all the houses in the village.  Eg.

algorithm					Using that data structure, devise an algorithm to compute the dot product between two sparse matrices.

algorithm					Magical binary strings are non-empty binary strings if the following two conditions are true: The number of 0's is equal to the number of 1's. For every prefix of the binary string, the number of 1's should not be less than the number of 0's. A magical string can contain multiple magical substrings. If two consecutive substrings are magical, then we can swap the substrings as long as the resulting string is still a magical string. Given a magical binary string, str, perform zero or more swap operations on its consecutive magical substrings such that the resulting string is aslexicographically large as possible. Two substrings are considered to be consecutive if the last character of the first substring occurs exactly one index before the first character of the second substring.  -----  Input Format a single binary string, str.  Constraints It is guaranteed that str is a binary string of 1's and 0's only. 1  length(str)  50 It is guaranteed that str is a magical string.  Output Format Find a string denoting the lexicographically largest magical string that can be formed from str.  Sample Input 0 11011000  Sample output 11100100  Explanation of sample Given the magical string str = 11011000, we can choose two consecutive magical substrings, 1100 and 10, to swap such that the resultant string, str' = 11100100, is the lexicographically largest possible magical string possible. Thus, we return the value of str', which is 11100100, as our answer.  .

algorithm					Given the root of a Binary Tree along with two integer values. Assume that both integers are present in the tree. Find the LCA (Least Common Ancestor) of the two nodes with values of the given integers. 2 pass solution is easy. You must solve this in a single pass.

algorithm					You are given 2 lists -  List 1: List<Demand> is a list of Demand objects. List 2: List<Supply> is a list of Supply objects.  Return a result fulfillment List<Demand,List<Supply>>.  This means each demand could be satisfied by more than one supplies.

algorithm					Given a string with only parenthesis. Check if the string is balanced. ex -  1) "<({()})[]> is balanced 2) "<({([)})[]> is not balanced

algorithm					Given an array of integers and a sum 'S'. Find 2 integers in the array that add up to S.

algorithm					Each test file starts with an integer t - the number of testcases. In each of the next t lines, you are given a string of n characters [ either ( or ) or * ].  Your task is to find the number of distinct balanced parentheses expressions you can make by replacing the * with either ( or ) or removing the * Note : You have to replace each * with one of  ( or ) or remove it. If removed, assume the string has reduced by 1 character. Duplicate strings are not allowed. The final expressions to be counted have to be distinct As the answer may be large, please output it modulo 1000000007 (10^9+7) Output one integer per line corresponding to each testcase. Constraints : 1 <= t <= 20 1 <= n <= 100 0 <= Number of * in the input string <= min(n,10)  Sample Input: 2 (*(*)*) *(*(**)* Sample Output 5 9 Explanation The five possible valid solutions are for the first input are : ((())) ()(()) ()()() (())() (()) The nine possible valid solutions are for the second input are : (((()))) (()(())) (()()()) (()()) ((())) ()(()) ()()() ()() (())

algorithm					/* # There's a room with a TV and people are coming in and out to watch it. The TV is on only when there's at least a person in the room. # For each person that comes in, we record the start and end time. We want to know for how long the TV has been on. In other words: # Given a list of arrays of time intervals, write a function that calculates the total amount of time covered by the intervals. # For example:  # input = [(1,4), (2,3)] # > 3 # input = [(4,6), (1,2)] # > 3 # input = [(1,4), (6,8), (2,4), (7,9), (10, 15)] # > 11 */

algorithm					find first not-repeating character by iterating through the length of the string only once and by using constant space.

algorithm					Given a string "2-4a0r7-4k", there are two dashes which we can split into 3 groups of length 1, 5, 2.   If we want each group to be length 4, then we get "24A0-R74k"  Given a String A and an int K, return a correctly formatted string.  IF A is "2-4A0r7-4k" and  B is 4, string is "24A0-R74K" IF K is 3, string is "24-A0R-74K" as the first grp could be shorter.

algorithm					determine whether a word is in a stored list; the list doesn't fit into memory; no disk access allowed, for lookups, memory access only; no false positives allowed, false negatives ok

algorithm					Find the shortest path between a start node and end node in a undirected +ve weighted graph. You are allowed to add at max one edge between any two nodes which are not directly connected to each other. ex:  From | To | Weight 1 2 2 1 4 4 2 3 1 3 4 3 4 5 1   start node = 1, end node = 5. extra edge weight = 2.

algorithm					Given infinite supply of coins of denominations 25, 10, 5 and 1, find the distinct number of ways to use the coins to sum up to the given value

algorithm					Given an array of 1 billion numbers with just a few 100 missing, find all the missing numbers. you have only enough memory to store only 10k elements

algorithm					Write a program to check whether it is a valid binary tree or not. Check all test cases (e.g. No left Node case).

algorithm					count the duplicates in a array of strings??

algorithm					Given an Array A with n elements. Pick maximum number of elements from given array following the rule: 1. We cannot pick A[i] and A[j] if absolute value of (A[i] - A[j]) > absolute value of (i - j)  Example: {13,5,4} Ans: 2 Pick 5 and 4.

algorithm					A frequent traveller collects all his travel tickets. A ticket has only 2 attributes, Start Journey Location name and Destination Name. Example from Delhi to Mumbai. At the end of the year, the traveller gets all his tickets together and tries to map his journey across the year. Print his travel route in a readable format. He does not remember his start location. Edit: he can visit a location multiple times, and can also go back and forth a place several times.

algorithm					Given a directed graph G, duplicate the graph using minimum space.

algorithm					A list of words is given and a bigger string given how can we find whether the string is a permutation of the smaller strings. eg- s= badactorgoodacting dict[]={'actor','bad','act','good'] FALSE eg- s= badactorgoodacting dict[]={'actor','bad','acting','good'] TRUE The smaller words themselves don't need to be permuted. The question is whether we can find a ordering of the smaller strings such that if concatenated in that order it gives the larger string One more constraint - some words from dict[] may also be left over unused

algorithm					Suppose you have a list of Dishes, where each dish is associated with a list of ingredients.  Group together dishes with  common ingredients.  E.g: Input:  "Pasta" -> ["Tomato Sauce", "Onions", "Garlic"] "Chicken Curry" --> ["Chicken", "Curry Sauce"] "Fried Rice" --> ["Rice", "Onions", "Nuts"] "Salad" --> ["Spinach", "Nuts"] "Sandwich" --> ["Cheese", "Bread"] "Quesadilla" --> ["Chicken", "Cheese"]  Output: ("Pasta", "Fried Rice") ("Fried Rice, "Salad") , ("Chicken Curry",  "Quesadilla") ("Sandwich", "Quesadilla")  Follow up:  What is the time and space complexity?

algorithm					Mr. Kim has to deliver refrigerators to N customers. From the office, he is going to visit all the customers and then return to his home. Each location of the office, his home, and the customers is given in the form of integer coordinates (x,y) (0x100, 0y100) . The distance between two arbitrary locations (x1, y1) and (x2, y2) is computed by |x1-x2| + |y1-y2|, where |x| denotes the absolute value of x; for instance, |3|=|-3|=3. The locations of the office, his home, and the customers are all distinct. You should plan an optimal way to visit all the N customers and return to his among all the possibilities.    You are given the locations of the office, Mr. Kims home, and the customers; the number of the customers is in the range of 5 to 10. Write a program that, starting at the office, finds a (the) shortest path visiting all the customers and returning to his home. Your program only have to report the distance of a (the) shortest path.     You dont have to solve this problem efficiently. You could find an answer by looking up all the possible ways. If you can look up all the possibilities well, you will get a perfect score.  [Constraints]  5N10. Each location (x,y) is in a bounded grid, 0x100, 0y100, and x, y are integers.    [Input]  You are given 10 test cases. Each test case consists of two lines; the first line has N, the number of the customers, and the following line enumerates the locations of the office, Mr. Kims home, and the customers in sequence. Each location consists of the coordinates (x,y), which is reprensented by x y.    [Output]  Output the 10 answers in 10 lines. Each line outputs the distance of a (the) shortest path. Each line looks like #x answer where x is the index of a test case. #x and answer are separated by a space.    [I/O Example]  Input (20 lines in total. In the first test case, the locations of the office and the home are (0, 0) and (100, 100) respectively, and the locations of the customers are (70, 40), (30, 10), (10, 5), (90, 70), (50, 20).)   5  Starting test case #1  0 0 100 100 70 40 30 10 10 5 90 70 50 20  6  Starting test case #2  88 81 85 80 19 22 31 15 27 29 30 10 20 26 5 14  10  Starting test case #3  39 9 97 61 35 93 62 64 96 39 36 36 9 59 59 96 61 7 64 43 43 58 1 36  ...       Output (10 lines in total)   #1 200  #2 304  #3 366

algorithm					Given two integer arrays list1 and list2 and an int target value. WAP to check if there exists such a sum, where one number taken from list1 and other from list2 to add up to become the target value. Return true if so, else return false.

algorithm					Given a sparse matrix, implement below two methods: void set(int row, int col, int val) /*Update value at given row and col*/  int sum(int row, int col) /*give sum from top left corner to given row, col  sub-matrix*/

algorithm					A company is looking for algorithm to show item recommendations.  If a customer bought A and B items and another buys A item, B should come as recommendations. There are two types of recommendations based on the connections 1) Two items are strongly connected if a customer buys those items. 2) Two items are weakly connected if each items are strongly/weakly connected to another third item.  Provided the sample input ABC  10  first:ABC first:HIJ sec:HIJ sec:KLM third:NOP fourth:ABC fourth:QRS first:DEF fifth:KLM fifth:TUV  first, sec, third.. represents the customer names ABC, HIJ... represents the item codes  For the Input item Id "ABC", since "ABC" is strongly connected to HIJ, DEF, QRS  and whereas ABC is weakly connected to KLM and TUV  the output should be count of strong and weak connection i.e., [3,2]

algorithm					Lets say someone accidentally deleted all the whitespaces from a sentence. Write a program to reconstruct the sentence from that stripped out string. Assume you have access to a dictionary function that returns if a given string is a valid word or not.  Example input: thisisavalidsentence Output: this is a valid sentence  If multiple solutions are possible, any one valid solution should be given. Assume there is always a valid solution. No invalid input will be given.

algorithm					* Given an unsorted integer array, place all zeros to the end of the array without changing the sequence of non-zero  * elements. (i.e. [1,3,0,8,12, 0, 4, 0,7] --> [1,3,8,12,4,7,0,0,0])

algorithm					Given a length n, return the number of strings of length n that can be made up of the letters 'a', 'b', and 'c', where there can only be a maximum of 1 'b's and can only have up to two consecutive 'c's  Example:  findStrings(3) returns 19 since the possible combinations are: aaa,aab,aac,aba,abc,aca,acb,baa,bac,bca,caa,cab,cac,cba,cbc,acc,bcc,cca,ccb and the invalid combinations are: abb,bab,bba,bbb,bbc,bcb,cbb,ccc

algorithm					Convert a number to English representation.  Ex: Input : 100 Output : One Hundred.

algorithm					There are n+1 loading docks. a permutation of boxes 1->n is placed on the first n. there is a fork that can move one box to an empty location at a time. Give an algorithm to sort then boxes with minimum number of moves.   Follow up: minimum distance

algorithm					Given a Pattern and a dictionary, print out all the strings that match the pattern. where a character in the pattern is mapped uniquely to a character in the dictionary ( this is what i was given first).  e.g 1. ("abc" , <"cdf", "too", "hgfdt" ,"paa">) -> output = "cdf"       2. ("acc" , <"cdf", "too", "hgfdt" ,"paa">) -> output = "too", "paa"

algorithm					We define a subarray of array to be a contiguous block of a's elements having a length that is less than or equal to the length of array a. For example, the subarray of array a = [1,2,3] are [1], [2], [1,2], [2,3], and [1,2,3]. Now, let's say we have an integer, k = 3. The subarrays of a having elements that sum to a number <=k are [1], [2], and [1,2]. The longest of these subarrays is [1,2], which had a length of 2.  Complete the maxLength function in the editor. It has 2 parameters :   1. An array of integers, a.   2. An integer, k The function must return the length of the longest subarray elements that sum to a number less than or equal to k.  Input Format Locked stub code in the editor reads the following input from stdin and passes it to the function: The first line contains a single ineteger n, denoting the number of elements in array a. Each line i of the n subsequent lines (where 0 <=i < n) contains an integer describing elements i in array a. Each line i of the n subsequent lines (where 0 <= i <= n) contains an integer describing elements i in array a. The last line contains an integer, k.  Constraints 1 <= n <= 10^5 1 <= a[i] < 10^3 1 <= k <= 10^9

algorithm					Swap the elements in Kth position from the start and end of a link list.  ex:  input: list: 1,2,4,5,7,8 	& 	 K=2 output: 1,7,4,5,2,8

algorithm					Given an array of numbers, find the maximum and minimum sum of sub sequences at a distance > m  Example   arr = {3, 4, -2, 1, -2, 4, 6, -3, 5} & m = 2  Solution  max = 13 {4 + 4 + 5}, min = -5 {-2-3}

algorithm					Given a string return the longest palindrome that can be constructed by removing or shuffling characters.  Example: 'aha'  -> 'aha' 'ttaatta' -> ' ttaaatt' 'abc' -> 'a' or 'b' or 'c' 'gggaaa' -> 'gaaag' or 'aggga'  Note if there are multiple correct answers you only need to return 1 palindrome.

algorithm					Find the height difference between two nodes in a binary tree.

algorithm					GIven a list of words, and the number of rows and columns, return the number of words that can be fit into the rows and columns by stringing together each consecutive word. If the next word doesn't fit in the same line, it should move to the next line. Find an efficient solution for this. For eg.  List of words: { "Do", "Run" } Number of columns: 9 Number of rows: 2  First row: "Do Run Do" (7 letters + 2 spaces fit into 9 columns) Second row: "Run Do" (Only 2 words fit into 9 columns)

algorithm					You want to design a Cab system which will show you nearest 5 taxis. Each taxi will continuously emit (x,y) coordinates. You need to print the nearest taxi from (p,q).

algorithm					You want to design a Cab system which will show you nearest 5 taxis. Each taxi will continuously emit (x,y) coordinates. You need to print the nearest 5 taxis from (p,q).

algorithm					You are given an old touch smartphone numbers having dial pad and calculator app.  The goal is to type a number on dialpad. Calculator have 1-9 and +,-,*,/,= as operations. But as phone is old, some of the numbers and some operations can't be touched. But you can always make a number using other numbers and operations. There could be multiple ways of making a number. You have to find minimum operation for making a number. For ex: lets say 1,4,6,7,8,9 works and +,-,* works. 2,3,5 and / doesn't work. If you have to type 18-> 2 operations. (Each touch is considered an operation) If you have to type 5 -> '1+4=' that requires 4 operations. There could be other ways to make '5'.  The goal is to find minimum operations.

algorithm					Given a read only array of n + 1 integers between 1 and n, find one number that repeats in linear time using less than O(n) space and traversing the stream sequentially O(1) times.

algorithm					Chess Knight Problem: - It deals with a knight piece on a chess board. You are given two inputs: starting location and ending location. The goal is to then calculate and print the shortest path that the knight can take to get to the target location.

algorithm					You are given a matrix with N rows and N columns. Elements in matrix can be either 1 or 0.  Each row and column of matrix is sorted in ascending order.  Find number of 0-s in the given matrix. Example:

algorithm					Alternate sorting: Given an array of integers, rearrange the array in such a way that the first element is first maximum and second element is first minimum.      Eg.) Input  : {1, 2, 3, 4, 5, 6, 7}          Output : {7, 1, 6, 2, 5, 3, 4}

algorithm					You have rand2() function which returns 0 or 1 with equal probability. You should implement rand3() using rand2().

algorithm					Given an array of n integers. MaxPrefix is defined as count of elements those are greater than the element and in the right side of array wrt to the element. Write a program to give the max of MaxPrefix Ex. Input 10 -4 6 2 8 9 4 Output is 5

algorithm					Write a class to take in a large arbitrary number, also provide a function to increment the number. The number will be passed on as an array of integers.

algorithm					Given a rectangle with top-left(a,b) and bottom-right(c,d) coordinates. Also given some coordinates (m,n) of sensors inside the rectangle. All sensors can sense in a circular region of radius r about their centre (m,n). Total N sensors are given. A player has to reach from left side of rectangle to its right side (i.e. he can start his journey from any point whose y coordinate is b and x coordinate is a<=x<=c. He has to end his journey to any point whose y coordinate is d and x coordinate is a<=x<=c).  Write an algorithm to find path (possibly shortest but not necessary) from start to end as described above.  Note: all coordinates are real numbers  (a,b) |----------------------------------------------| |.......................................................|end |.......................................................| |start................................................| |.......................................................| |----------------------------------------------|(c,d)  Edit: You have to avoid sensors. Also u can move in any direction any time.

algorithm					# take an array and print non over lapping in order pairs. example:

algorithm					You are given a range [first, last], initially white. You need to paint it black.  For this purpose you have a set of triples [(f, l, cost), ...] - where each triple means that you can paint range [f, l] for `cost` coins (limitations: cost is floating point >= 0, f, l, first, last are integers). Find minimum cost needed to paint the whole range [first, last] or return -1 if it's impossible Example:

algorithm					Given an array of length N and an integer K, sort the array as much as possible such that no element travels more than k positions to its left - an element however can travel as much as it likes to its right.

algorithm					Given a binary tree, whose leaf nodes are connected,               1            /  \           2   3         /   \  /  	4  5 6 Now 4,5,6 are leaf nodes in the above BT, 4->5->6  4's left is pointing to 6 and 6's right is pointing to 4. We have a circular DLL of leaf nodes.  We need to find the height of this tree?

algorithm					given 2 strings A and B. generate all possible solutions when B is merged in A. Ex: A =  "hey" B: "sam" then solutions are :  heysam,hseaym,hesaym,sahemy etc.  notice that order should be the same for both of strings while merging.

algorithm					A museum was represented by a square matrix that was filled with O, G, and W where O represented open space G represented guards, and W represented walls. Write a function that accepts the square matrix and returns another square matrix where all of the O's in the matrix are replaced with the number of how many spaces they are away from a guard, without being able to go through any walls.

algorithm					You are given a string "abc" which is encoded like "123" where alphabets are mapped like a => 1 to z => 26. Now find out how many string can be formed by reverse engineering encode string "123".  For ex. given string "123"  we can form 3 string "abc"(1,2,3), "lc" (i.e 12,3), "aw"(1,23).  for string "1234" we have following possible combinations, I might be missing some of them but you get the idea   {12, 3, 4} {1, 23, 4} {1, 2, 3, 4}

algorithm					Select Kth largest value in the array. Given an unsorted array of size n, and a value k. Select the kth largest value from the array.  For example:  Array is [5, 3, 9, 1], n is 4 k = 0 => 9 k = 1 => 5 k = 3 => 1

algorithm					Write a program to find all duplicate files within a folder.

algorithm					WAP to take one element from each of the array add it to the target sum. Print all those three-element combinations.  /* A = [1, 2, 3, 3] B = [2, 3, 3, 4] C = [1, 2, 2, 2] target = 7 */  Result: [[1, 2, 4], [1, 3, 3], [1, 3, 3], [1, 3, 3], [1, 3, 3], [1, 4, 2], [2, 2, 3], [2, 2, 3], [2, 3, 2], [2, 3, 2], [3, 2, 2], [3, 2, 2]]

algorithm					You are designing a system the records website visits. The interface for this system is:  void recordHit(); long getCount();  `getCount()` returns the amount of hits to the site for only the last 5 minutes.   Your task is to code `recordHit()` and `getCount()`

algorithm					This is a question I received in an online challenge. A list of numbers are given. We need to find the total number of groups in which the digits of each number have same frequency. For example if numbers are: 1 10 3 33  There are 4 groups:  G1={1}has one 1.  G2={3} has one 3.  G3={10}has one 1 and one 0.  G4={33}as two 3s.

algorithm					Find the anagrams from a list of strings  Input : {"tea", "ate", "eat", "apple", "java", "vaja", "cut", "utc"} Output : {"tea", "ate", "eat","java", "vaja", "cut", "utc"}

algorithm					You are given a graph, some edges are black, some are red. Find a spanning tree with one restriction: if we take some node as root, every path from it to some leaf node must consist of alternating red-black-red-black edges. That is, no path from root to leaf must contain sequential black-black edges or red-red edges. You are guaranteed that such spanning tree exists.

algorithm					Given a string S, print the longest substring P such that P > S lexicographically. You may assume that such substring exists.

algorithm					Given a number print the number of combinations you can derive from the number. 1=A, 2=B, 26=Z, 0=+.  For example: 1123 can be represented by  1,1,2,3 which would stand for AABC.  Another representation - 11,23 - JW Another representation - 1,1,23 - AAW Another representation - 11,2,3 - JBC  For number 1123, there will be 5 combinations.

algorithm					what is the best sorting algorithm in terms of complexity and why?

algorithm					Given a million list of co-ordinates in the form of longitude and latitude just as Google maps .How will you print closest k cities to a given location .

algorithm					Given a 2D matrix of integers, sort it such that:   - every row is sorted in ascending order from left to right  - every column is sorted in ascending order from top to down  - all items in the same row are unique  You may assume the input matrix is always valid, meaning that such a sort is always possible.  For example: for input matrix

algorithm					|X			XX			|  |	X		X			|  |	X					|  |						|

algorithm					Given a string where in each word letters were randomly shuffled and after that words were written without spaces (lets call it X). Also you have a dictionary. The task is to return all possible strings S that can be transformed into the string X and all words in S are from dictionary.

algorithm					Given an array of 0s and 1s, and k, Find the longest continuous streak of 1s after flipping k 0s to 1s.   E.x  array is {1,1,0,0,1,1,1,0,1,1}  k = 1 (which means we can flip k one 0 to 1)  Answer: 6 (if we flip 0 at index 7, we get the longest continuous streak of 1s having length 6)

algorithm					Given two arrays/Lists (choose whatever you want to) with sorted and non intersecting intervals. Merge them to get a new sorted non intersecting array/list.  Eg: Given: Arr1 = [3-11, 17-25, 58-73]; Arr2 = [6-18, 40-47];  Wanted: Arr3 = [3-25, 40-47, 58-73];

algorithm					Define a function that can detect whether the characters of a string can be shuffled without repeating same characters as one other's neighbors. E.g. :  apple >> alpep, so valid a >> a, valid aa >> aa, invalid/impossible aab >> aba, valid aaaabbcc >> acabacab, valid etc. You do not have to find one representation, just have to detect if it is possible or not!

algorithm					Check if an integer array is arithmetic sequence.  Example: 1, 2, 3, 4, 5, 6, 7, 8 => true 		1, 3, 5, 7, 9 => true  Array may not be sorted.

algorithm					Second Least common element from an Integer array.   Example:   [5,5,4,5,4,6,6,6,1,3,3,4,4,5,4]   Answer: 3   Reason: {1=1, 3=2, 4=5, 5=4, 6=3}

algorithm					Task schedule: given a sequence of task like A B C(means 3 different tasks), and a coldtime, which means you need to wait for that much time to start next  [same] task. Now----  Input: string, n Output: the best task-finishing sequence.  eg. input: AAABBB, 2 Output: AB_AB_AB ( "_" represents do nothing and wait)

algorithm					You are given a function bool rand_bit_p() that returns true with some unknown probability p and false with probability 1 - p. Write function rand_bit() using rand_bit_p that will return true and false with equal probability (that is, implement a fair coin, given unfair coin)

algorithm					Given an array and an integer k, find the maximum for each and every contiguous subarray of size k.(Using DP)

algorithm					Given a non-directed, strongly connected graph where the node values are letters of the alphabet, write an algorithm that prints out all possible permutations of strings. What is this called? For example: V = A,B,C Printout ABC ACB BAC BCA CAB CBA BAC etc.

algorithm					Given a sorted integer array, write a method that builds a balanced binary search tree. What is the runtime complexity? Hint: Recursion. Follow-up: Non-recursive solution

algorithm					Given a decimal number, write a function that returns its negabinary (i.e. negative 2-base) representation as a string.

algorithm					Given 4 teams and 3 gamedays, create an algorithm such that each team plays another team every gameday and by the end of the 3 game days each team should have played one game with every other team.

algorithm					Given a number (integer) as a string turn in into a number:  E.g. "One million two hundreds thousands fifty seven" => shoud return 1200057.  How to model it and how to test it? What data structures would you use. Deep testing (corner cases)

algorithm					Given a number N, write all possible sums of consecutive numbers that add up to N.  That is: return all pairs (a, k) such that a+(a+1)+...+(a+k)=n  After that: 1. what if N is negative or a is negative; 2. what if N is real and the possible implications of this

algorithm					Given an undirected graph and a node, modify the graph into a directed graph such that, any path leads to one particular node.

algorithm					Find if a given binary tree has duplicate sub trees or not. (Two leaf nodes of a parent do not count as subtree)

algorithm					Image an airport with the control tower having a constantly rotating radar scanning for airplanes. The radar's coordinates in the 2-d plane are (0,0). The radar has an API: void scan(const Plane &P) that is called periodically whenever the radar detects a plane. You can imagine that the  Plane structure has x,y coordinates for that plane. You should fill in the function Scan, such that at any given time you are able to return the 100 closest planes to the tower (0,0).

algorithm					Find missing element in the A.P.

algorithm					Given integer k and a subset S of set {0, 1, 2, ..., 2^k - 1} Return the count of pairs (a, b) where a and b are from S and (a < b) and (a & b == a) & here is bit-wise and. Do it faster than O((2^k)^2), assume k <= 16  Example: 0b111 0b101 0b010 Answer: 2  0b110 0b011 0b101 Answer: 0

algorithm					We have a long string. We label some substrings with tags.   - A tag entry is [startIndex, endIndex, tag]. - Query: 1 or more tags - Output: all blocks/ranges with all queried tags.  Example tag entries:      [23, 72, 0]	// label [23, 72) with tag 0     [34, 53, 1]	// label [34, 53) with tag 1     [100, 128, 0]  Query and Output:      0 => [23, 72], [100, 128]     0,1 => [34,53]	// [34, 53) matches both tag 0 and 1  Give an efficient algorithm. Please describe your algorithm before posting code.  **Edit**: To add some difficulties, partial overlap is treated the same as full overlap, ONLY the overlapped part matches both tags. E.g. if we have entries:      [23, 72, 0]	// label [23, 72) with tag 0     [10, 53, 1]	// label [34, 53) with tag 1  Query and Output:     0,1 => [23,53]	// [23, 53) matches both tag 0 and 1  Minor detials: Note in the comments we used open range on the right, i.e. if the string named "str", [23, 72, 0] includes str[23] but NOT str[72]; and there's no overlap between the following entries: [23, 72, 0] [10, 23, 0]

algorithm					Given a binary tree print it in inward spiral order i.e first print level 1, then level n, then level 2, then n-1 and so on.  For Ex -               				1       				2		           3 			4           5               6         7                 8          9   10   11     12   13   14 15  Print-  1 15 14 13 12 11 10 9 8 2 3 7 6 5 4  Follow up question - Extend the algorithm to n-ary tree.

algorithm					You know result of a soccer match, print all the possible ways that this game ends up with this result.  Example: final score 1 - 1:  0 - 0  0 - 1 1 - 1  0 - 0 1 - 0 1 - 1  Another example if the final score is 2 - 3 there are many possibilities for reaching to that score:  2 - 3  0 - 0 1 - 0 2 - 0 2 - 1 2 - 2 2 - 3  0 - 0 1 - 0 1 - 1 1 - 2 2 - 2 2 - 3  0 - 0 0 - 1 0 - 2 0 - 3 ...

algorithm					Given a singly connected linked list, find the largest palindrome in the list in O(1) space.

algorithm					Given a linked list consisting of String in each Node . Given just a pointer to the head Node find whether the resultant String formed by combining all the Nodes of the linked list is a palindrome or not in O(1) space and O(n) time.  eg  Consider this linked List structure  aba -> cd -> efe -> d -> caba  Hence this structure is palindrome .

algorithm					Face to face  Q3) stream of numbers coming, get 'n' min elements at any point of time

algorithm					Given a long string s and short strings t1, t2, t3 (which can have different length) find the shortest substring of s which contains t1, t2 and t3.

algorithm					Given N balloons, if you burst ith balloon you get Ai1AiAi+1 coins and then (i-1)th and (i+1)th balloons become adjacent. Find maximum number of coins you can gather.  Assume that we have extra 1 at left most and right most positions. (don't take in answer just for boundary positions)  Hence if we have left or right boundary positions we multiply 1.

algorithm					for given array

algorithm					We have an iterator class as below:

algorithm					Google is conducting a contest where they display a special doodle to the user submitting the billionth query of the day. Design a system to achieve this. (NOTE: Google has thousands of servers and each query can hit a different server). Optimise it. How will you handle server failures?

algorithm					You are given two arrays of length M and N having elements in range 0-9.Your task is to create maximum number of length K  from elements of these two arrays such that relative order of elements is same in the final number as in the array, they are taken from i.e.  If two elements a,b are taken from array1 and and a comes before b in array1 so in the final number a should come before b (Relative order kept same) . Example: N=4 and M =6                 Array1 = { 3 , 4 , 6,5}                 Array2 ={9,1,2,5,8,3} Suppose K = 5, then number will be {9,8,6,5,3}  You can see {9,8,3} are taken from array2 in the same order as they are in Array2. Similarly {6,5} are taken from Array1 in the same order and number 98653 is maximum possible number.

algorithm					I had two interviews with Google  first) one with US person...he asked decent question with lot of hints...experience : positive  and  then second) interview with person from India...I prepared for one month but he asked me very tough one graph/tree question...never gave single hint and based on that one question he judged my seven years of experience in Software Development (I never experienced what they say...Google looks for approach and not final answer)     Q.1 : Arrange array in wave form A1 > a2 < a3 > a4 ... O(n.log-n) (Note: its not A1 >= A2)  Q.2 : Given Graph with Tree characteristics, find one node as root so that height of tree will  be minimum

algorithm					Given a 4*n block, find number of different ways of filling it with 1*2 smaller blocks. Rotation of smaller blocks is allowed.

algorithm					Given an array of numbers, for every index i, find nearest index j such that a[j] > a[i].If such an index doesnt exist for i, 1 should be printed.

algorithm					Imagine a man reading a book. He can perform only 2 possible actions of reading:  1) read a page in a minute (careful reading),  2) read two pages in a minute (look through). Nothing else is permitted. Calculate the number of all possible combinations of book reading ways with given number of pages. Example: given 3 pages. Answer is 3 combinations, as follows:  1st: Careful reading (1) - careful reading (1) - careful reading (1), 2nd: Careful reading (1) - look through (2), 3rd: Look through (2) - careful reading (1).

algorithm					Given-an-array-of-length-n-having-integers-0-to-n-1-in-unsorted-order-we-have-to-modify-this-array-such-that-the-value-at-a-n-becomes-a-a-n-for-example-if-a-0-contains-5-then-a-0-will-have-value-a-5-and-so-on-condition-is-that-this-should-take-O-n-time-complexity

algorithm					What is the fastest way to compute cube root?

algorithm					Write a function to test if the given set of brackets are balanced or not. e.g. {{}}{)([][]

algorithm					Check given Number is same after 180 degree rotation?  i/p:  69 o/p: True  i/p:  916 o/p: True  i/p:  123 o/p: False

algorithm					How do we achieve (google news) personalization.

algorithm					Given a random string S and another string T with unique elements, find the minimum consecutive sub-string of S such that it contains all the elements in T. example: S='adobecodebanc' T='abc' answer='banc'

algorithm					Given an infinite stream of characters and a list L of strings, create a function that calls an external API when a word in L is recognized during the processing of the stream.  Example: L = ["ok","test","one","try","trying"] stream = a,b,c,o,k,d,e,f,t,r,y,i,n,g.............  the call to external API (let's call it some function callAPI()) would be called when the 'k' is encountered, again when the 'y' is encountered, and again at 'g'.

algorithm					There is a circular train (the head is connected to the tail) where each car of the train contains a light bulb. Initially, the bulbs are randomly switched on/off.   You need to determine the size of the train (the number of cars)  by going from one car to another and switching the light bulbs

algorithm					Given a prime set, we call "prime expressible" if a number can be factorized only using given prime numbers. Find n-th big expressible number.   E.g., prime set = {2, 3}  expressible number = {1,2,3,4,6,8, 9, 12...}  non-expressible number = {5, 10... }   The primes in the prime set are ordered in an increasing order, and can include a prime < 10^4 (don't remember the exact range), and n can also be as large as 1-10^6.

algorithm					Given an array of positive integers (excluding zero) and a target number. Detect whether there is a set of consecutive elements in the array that add up to the target.  Example: a = {1, 3, 5, 7, 9} target  = 8  output = true ({3, 5})  or target = 15 output = true : {3, 5, 8}  but if target = 6, output would be false. since 1 and 5 are not next to each other.

algorithm					Given a dictionary containing a list of words, a starting word, and an ending word, return the minimum number of steps to transform the starting word into the ending word.    A step involves changing one letter at a time to a valid word that is present in the dictionary.  Return null if it is impossible to transform the starting word into the ending word using the dictionary.  Example:  Starting word: cat Ending word: dog  cat -> cot -> cog -> dog ('cot' and 'cog' are in the dictionary)  return 3

algorithm					Write a function to detect the number of cycles in a directed graph. The graph is passed as an adjacency matrix.

algorithm					Given an array of elements, return an array of values pertaining to how many elements are greater than that element remaining in the array.  Brute force is obvious, but must be done faster than O(n^2)  Ex.  [3,4,5,9,2,1, 3] Return [3, 2, 1, 0, 1, 1, 0] First element is 3 because 3<4,5,9.  Second element is 2 because 4< 5,9 etc

algorithm					Given a set of values 0-9, return all permutations of that set of length n.  Example:  n=2, set ={2,3,4} Return: {2,2}, {3,3}, {4,4}, {2,3}, {3,2}, {3,4}, {4,3}, {2,4}, {4,2}

algorithm					Given a pattern and a string, return a boolean of whether the string matches the pattern.  Each character in pattern represents one of more characters in string.  Method: is_match(pattern, string)   Sample Testcases   is_match('abba', 'dogfishfishdog') -> True  is_match('aba', 'dogfishdog') -> True  is_match('a', 'acdefghijk') -> True  is_match('ab', 'acdefghijk') -> True    is_match('aba', 'dogfishfish') -> False  is_match('aba', 'dogfishhorse') -> False   Preferable use Python, and say the Big O runtime and space.

algorithm					Given a string and two words which are present in the string, find the minimum distance between the words Eg: "the brown qucik frog quick the", "the" "quick" O/P -> 1 "the quick the brown quick brown the frog", "the" "the" O/P -> 2

algorithm					Given a linkedlist, write an algorithm to divide the linkedlist into two linkedlists, the first contains the Fibonacci numbers in the list and the second contains the non-Fibonacci numbers. Test the algorithm after developing the code

algorithm					You are given a set of points on x axis (consumers) Also you are given a set of points on a plane (producer)  For every consumer print the nearest producer. Wanted something better than O(n^2) time.  Example: consumers: 1 5 7 producers: (0, 3), (1,1), (3, 2), (8, 10), (9, 100)  Answer: for 1 nearest producer is (1, 1), for 5 nearest is (3, 2), for 7 nearest is (3, 2)  Follow-up question: now both sets are sorted by x coordinate. Could you come up with a linear algorithm?

algorithm					Find a counter example proving that the following substring algorithm is incorrect:

algorithm					Input argument of a method is a list of char array. The method have to print all the possible combination of input char(s)...For example if the input argument has ['A','B','C','D'] the output should be A,B,C,AB,AC,AD,BC,BD,CD,ABC,ACD,BCD,ABCD

algorithm					Given an array of "array range", return an optimized array by deleting subarrays.   NOTE: Array range (2,6) represents (2,3,4,5,6)  INPUT: [(2,6),(3,5),(7,21),(20,21)] OUTPUT: [(2,6),(7,21)]   Reason: (3,5) is a subarray of (2,6) and (20,21) is a subarray of (7,21)

algorithm					Given a sentence in a form of a string, reverse the words in the string and return a string. Handle a case where there might be period at the end of the sentence. If there is a period, the period has to come to the end of the reversed sentence. Discuss the time complexity of your algorithm.    INPUT: "This is a sentence" OUTPUT: "sentence a is This"  INPUT2: "This one has period." OUTPUT2: "period has one This."

algorithm					1. Balanced Parentheses  Given a string s of parentheses (ex: (()), return the minimum number of parentheses that need to be inserted to make it into a well formed string A well formed (balanced) string of parentheses is defined by the following rules:  The empty string is well formed.  If s is a well formed string, (s) is a well formed string.  If s1 and s2 are well formed strings, their concatenation s1s2 is a well formed string. Implement   int MinNumInsersertionsForBalancing(const string& s)

algorithm					Sort an array of 0s, 1s and 2s Given an array A[] consisting 0s, 1s and 2s, write a function that sorts A[]. The functions should put all 0s first, then all 1s and all 2s in last.  Example Input = {0, 1, 1, 0, 1, 2, 1, 2, 0, 0, 0, 1}; Output = {0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2}  The problem is similar to http://www.csse.monash.edu.au/~lloyd/tildeAlgDS/Sort/Flag/  But they have added 1 trick into the question, You cannot use high = n;  It means don't calculate the length of array.  Can anyone help me in writing the code for this problem ?

algorithm					Rearrange characters in a string so that no character repeats twice.   Input: aaabc  Output: abaca   Input: aa  Output: No valid output   Input: aaaabc  Output: No valid output

algorithm					There are several people sitting in the cinema, some of them are couples, some are not, they decide to swap their seats so that the couples can seat together, please calculate the minimal swap numbers. 1. the swap can happen between any two position. 2. E.g. AABCCDB -> AADCCBB, ans is 1

algorithm					there are N cities (numbered from 1 to N) in the game and connect them by N-1 highways. It is guaranteed that each pair of cities are connected by the highways directly or indirectly.The game has a very important value called Total Highway Distance (THD) which is the total distances of all pairs of cities. Suppose there are 3 cities and 2 highways. The highway between City 1 and City 2 is 200 miles and the highway between City 2 and City 3 is 300 miles. So the THD is 1000(200 + 500 + 300) miles because the distances between City 1 and City 2, City 1 and City 3, City 2 and City 3 are 200 miles, 500 miles and 300 miles respectively.  During the game the length of some highways may change. you want to know the latest THD.  sample input 3 5 1 2 2 2 3 3 QUERY EDIT 1 2 4 QUERY EDIT 2 3 2 QUERY  sample output 10 14 12

algorithm					You are given a permutation arr[N]. E.g. arr[3] = {2, 1, 0} or arr[5] = {0,1,2,4,3}; Then you can prepare somehow and then start serving requests: request(a, b, k) = sorted(arr[a:b])[k], that is, k-th order statistic on slice [a:b] of arr. E.g. if arr is [3,4,5,0,1,2] and a = 2 and b = 5, then arr[a:b] = [5,0,1] and let k = 2, so we sort it - get [0,1,5] and take k-th element, that is - 5.  Implement request(a, b, k) function. You can preprocess input data, that is, assume there will be only one array and many request() calls.

algorithm					Given a string which may contain parenthesis. We must verify the validity of the string. ex-  1) "<ad675+-fkmfd>" is a valid string 2) "<[((kskfhdbh7)" is invalid 3) "[<<((shfs8))>>]" is valid  Extension to the question -  Suppose you had a hash table that told you how a parenthesis starts and how it ends as a key value pair, how would you then validate the string. ex - <key,value> = < '(' , ')' > indicates '(' is a start parenthesis and ')' should be the end of that paranthesis. <'A','&'> indicates that 'A' is a start parenthesis and '&' is the end parenthesis.  Note: Validity means a parenthesis that starts, must end.

algorithm					Find the largest substring palindrome in a given string. ex: input: abbac output: abba  Solution: Use Hashmap

algorithm					Design and implement the constructor for the minesweeper game that takes in the dimension of the field and number of mines as input

algorithm					You are given large numbers of logs, each one of which contains a start time (long), end time (long) and memory usage (int). The time is recorded as MMDDHH (100317 means October 3rd 5PM) Write an algorithm that returns a specific time (hour) when the memory usage is the highest. If there are multiple answers, return the first hour.  e.g. 100207 100208 2        100305 100307 5        100207 100209 4        111515 121212 1 Answer: 100207  (Need to consider different scenarios like the time slots could be very sparse)

algorithm					Print first and last node of all the levels of a tree. Ex if tree is -  root->data = 1 root->left->data = 2 root->right->data = 3 root->left->right->data = 4 root->right->right->data = 6 root->right->left->data = 5 root->right->left->left->data = 7 root->right->left->left->right->data = 8  Output - 1 2 3 4 6 7 8

algorithm					Write a program to process the matrix. If an element is 0 at ith row and jth column, then make the whole ith row and jth column to 0.  Constraints: Space complexity should be O(1) Time complexity - Only single pass is allowed. Note that single pass is not O(n). This is single pass : An element will read and written only ones.  Edit:  Recursion is not allowed since it is O(n) space on stack

algorithm					Given three arrays A,B,C containing unsorted numbers. Find three numbers a, b, c from each of array A, B, C such that |a-b|+|b-c| +|c-a| is minimum.

algorithm					Given an array of task and k wait time for which a repeated task needs to wait k time to execute again. return overall unit time it will take to complete all the task.  Example:  1. A B C D and k = 3 ans: 4 (execute order A B C D) 2. A B A D and k = 3 ans: 6 (execute order A B . . A D) 3. A A A A and k =3  ans: 13 (A . . . A . . . A . . . A) 4. A B C A C B D A and k = 4 ans: 11 (A B C . . A .C B D A )

algorithm					Post order traversal for an N-ary tree iterative way. Given, struct Node {    int val;    vector<Node*> children; };  Without modifying original structure.

algorithm					. Given n strings consisting of R and B. Two strings can be only combined if last character of first string and first character of second string are same. Given n strings, you have to output the maximum length possible by combining strings.  I/P RBR BBR RRR output : 9

algorithm					Design an algorithm to find all the common elements in two sorted lists of numbers. For example, for the lists 2, 5, 5, 5 and 2, 2, 3, 5, 5, 7, the output should be 2, 5, 5.

algorithm					Given a string which only contains lowercase. You need delete the repeated letters only leave one, and try to make the lexicographical order of new string  is smallest. i.e: bcabc You need delete 1 'b' and 1 'c', so you delete the first 'b' and first 'c', the new string will be abc which is smallest.  ps: If you try to use greedy algorithm to solve this problem, you must sure that you could pass this case: cbacdcbc. answer is  acdb not adcb  I can't solve this problem well and the interviewer said that you can scan the string twice. First scan is do some preprocess, and the second is to get the answer, but I really can't come up this idea.

algorithm					$a = [3, 1, 4, 5, 19, 6];

algorithm					You are given a list of n float numbers x_1, x_2, x_3, ... x_n, where x_i > 0. A traveler starts at point (0, 0) and moves x_1 metres to the north, then x_2 metres to the west, x_3 to the south, x_4 to the east and so on (after each move his direction changes counter-clockwise) Write an single-pass algorithm that  uses O(1) memory  to determine, if the travelers  path crosses itself, or not (i.e. if it's self-intersecting) e.g. 2 1 1 2 -> crosses 1 2 3 4 -> doesn't cross

algorithm					BST is given. Calculate and return array with a sum of every level. For example,  	   1      2         3   4    5    1   2  Output should be [1, 5, 12].

algorithm					Given an array of positive integers(>0) , you have to insert '+','*','(',')' signs basically plus multiply and brackets such that value of resultant expression becomes maximum. Hint: Consider case of continuous ones  You have to print the resulting expression

algorithm					Write all solutions for a^3+b^3 = c^3 + d^3, where a, b, c, d lie between [0, 10^5] in at least O(n^2) complexity

algorithm					Given a binary N X N matrix, return the size of the largest '+' of ones.   input: 0 0 0 0 1 1 0 1 1 1 1 1 1 1 1 0  output:  5   (binary search is not allowed)

algorithm					This is one of the interview questions during the Amazon SDE interview. Request your help in providing the solution. Question - We are interested in building a special type of sequence. for a given number N, we want to arrange the numbers {1,1,2,2,3,3,... N,N} such that they have the following property. For each number / in (1,N) there should be exactly / numbers between the first appearance of the number and the second appearance. Below example would clarify further.  Input: A Single number N for which we want to produce the sequence.  Output: A space separated list of sequence or NA if there is no possible sequence.  Example Input: 3  Example Output: 2 3 1 2 1 3  Explanation : There is 1 number between 1s(2). There are 2 numbers between the 2's(3 1 ). There are 3 numbers between the 3's(1 2 1 ).

algorithm					I came across this problem online.  > Given an integer:N and an array int arr[], you have to add some > elements to the array so that you can generate from 1 to N by using > (add) the elements in the array.  Please keep in mind that you can only use each element in the array once when generating a certain x (1<=x<=N). Return the count of the least adding numbers.      For example:      N=6, arr = [1, 3]       1 is already in arr.       add 2 to the arr.       3 is already in arr       4 = 1 + 3       5 = 2 + 3       6 = 1 + 2 + 3       So we return 1 since we only need to add one element which is 2.  Can anyone give some hints?

algorithm					Device an algorithm to find duplicates in array where each duplicate can occur k times. The algorithm must be of O(n) time and space complexity at max

algorithm					On a given array with N numbers, find subset of size M (exactly M elements) that equal to SUM.

algorithm					Given an array A with n integers. Rearrange array such that A[0]<=A[1]>=A[2]<=A[3]>=A[4]<=A[5] and so on  Edit: Array is not sorted  You have to do it in linear time O(N)

algorithm					Generate all possible sorted arrays from alternate elements of two given sorted arrays.  Given two sorted arrays A and B, generate all possible arrays such that once first element is taken from A then from B then from A and so on in increasing order till the arrays exhausted. Then first element is taken from B then From A, and do same as above.

algorithm					Find an algorithm to find a word ladder between 2 words by changing just one letter at a time. All the words formed should be valid dictionary words. Eg.  FOOL ->POOL->POLL->POLE->PALE->SALE->SAGE COLD  CORD  CARD  WARD  WARM

algorithm					Write a program in that determines the members and parents of nested groups without using recursion.  These are the requirements.  1. A group can have 0 or more members. 2. A group can be member of one or more groups 3. A group can be member of itself. 4. If there is a path from a group either directly or through multiple hops, then that user is considered as member of the group. 5. A group can have users or groups as members  EX: Input looks like this

algorithm					Reverse string except spaces. A string has mix of alphabets and spaces. Your task is to reverse the string, but preserve the positions of spaces. For example, reverse of " a if" is " f ia".

algorithm					Given a matrix containing 0 and 1. Consider 1 as 'Land' and 0 as 'Water'. Find out the number of 'Islands' in the matrix. That is, set of all adjacent 1 will make up for an island.  For example:  [ 0 1 1 0 1 ] [ 1 1 1 0 0 ] [ 0 0 0 1 1 ] [ 1 0 0 1 0 ]  This problem has 4 islands. ( consider set of 1s, vertically, horizontally and diagonally ).

algorithm					Given an unbalanced binary tree, write code to select a node at random (each node has an equal probability of being selected).

algorithm					Find a duplicates in an array of length n. The values are positive integers in the range between 1 .. n-1

algorithm					Count triangles in an undirected graph where a triangle is a unique set of three vertices connected to one another.

algorithm					Given two sorted arrays find the element which would be N-th in their merged and sorted combination.

algorithm					Given a BST with unique values find in a given tree a value closest to a given value X.

algorithm					A car rental company which rents car by per hour basis  wants to know the time period for maximum number cars that are rented. ie you are given the list of rental start time and return times of all rented cars in the day  for all cars in a day find the maximum time period in which cars are on the road.

algorithm					Round 6 Question 3 : You are given a word document, you have to print the words with frequencies. Now print the kth rank word in terms of frequency. Print top k words as well by frequencies

algorithm					The "surpasser" of an element in an array is defined as the number of elements that are to the "right" and  bigger than itself.  Example: Array: [2, 7, 5, 5, 2, 7, 0, 8, 1]  The "surpassers" are  [5, 1, 2, 2, 2, 1, 2, 0, 0]  Question: Find the maximum surpasser of the array.  In this example, maximum surpasser = 5

algorithm					Find the longest common prefix in a list of phrases. For instance; "i love all dogs", "i love cats" should return "i love".

algorithm					How will you serialize the binary tree ?

algorithm					There's a function that concatenates two strings and returns the length of the resultant string. When called upon a series of strings how do we minimize the cost of using this function. Let's say we have 3 strings, A= "abc", B="def", C = "gh". Now cost of merging AB = 6 and cost of merging the resultant string with C is 8. Thus the total cost is 6 + 8 = 14. However, if we merge A and C, then the cost is 5 and then merge B with this, the cost is 8, so the total cost is 13.  Find an algorithm that minimizes the cost of adding such a series of strings.

algorithm					Given a binary tree, implement an iterator that will iterate through its elements.

algorithm					Given a binary tree (not search tree), find the path which adds up to given sum.

algorithm					Tech Screening Question 1 : You will be given a stream of integers, and a integer k for window size, you will only receive the streams integers one by one. whenever you receive an integer, you have to return the maximum number among last k integers inclusive of current entry.  Interviewer was expecting O(N) solution for N asks.  Edits: Interviewer was expecting O(N) Time + O(1) avg case space complexity solution for N asks. and integers are not given in a array, every time only one integer will be passed as input to your method.

algorithm					Print the level of friendship.  Given a person and list of his friends, print all his friends by level of association.  The text file will be like one below  A: B,C,D D: B,E,F E: C,F,G  If the input is A, the out put should be:  Level 1 - B,C,D Level 2 - E,F Level 3 - G

algorithm					Given a start string, end string and a set of strings, find if there exists a path between the start string and end string via the set of strings.  A path exists if we can get from start string to end string by changing (no addition/removal) only one character at a time. The restriction is that the new string generated after changing one character has to be in the set.  start: "cog"  end: "bad" set: ["bag", "cag", "cat", "fag", "con", "rat", "sat", "fog"] one of the paths: "cog" -> "fog" -> "fag" -> "bag" -> "bad"

algorithm					You are given a bunch of nodes evenly spaced in a rectangular shape. The rectangle is M nodes long and N nodes wide. Node A is in the upper left hand corner and node B is at the bottom right hand corner. How many different paths are there from A to B?  What is a brute-force solution? What is better than a brute force solution?

algorithm					std C library has pow(x, n) function - implement that function

algorithm					Shuffle a given array such that each position is equally likely.

algorithm					Given a max-heap represented as an array, return the kth largest element without modifying the heap. I was asked to do it in linear time, but was told it can be done in log time.

algorithm					Given a file, read last n lines from the file  string ReadNLines(sttring fileName, int n);

algorithm					Assume we have a very large file containing millions of lines of data. Only 2 lines are identical, rest are unique. Each line is long enough that they may not fit in memory. Design an efficient algorithm to determine identical lines? And, then generalize it for 'n' identical lines.

algorithm					Description  A prospective CS student is investigating how many semesters it will take to graduate from a variety of different universities. Each university provides a list of required courses, their prerequisites, and when each course is offered. Given this information, determine the minimum number of semesters to graduate.  Consider the following example. A student is required to take 4 courses, mt42, cs123, cs456, and cs789. mt42 is only offered in the fall semester and has no prerequisites. Similarly, cs123 is only offered in the spring semester and has no prerequisites. cs456 is only offered in the spring semester and has both cs123 and mt42 as prerequisites. Finally, cs789 is offered in both fall and spring and has cs456 as its only prerequisite. The shortest time to graduate is 5 semesters, by taking mt42 in the fall, cs123 in the next spring, cs456 the following spring (since it is not offered in the fall) and finally cs789 the following fall.  For this problem, there are only two semesters, fall and spring. Always start counting semesters from the fall.  In addition to the fall/spring scheduling issues, there is one slight complication. In order to keep the dormitories full, each university limits the number of courses that can be taken in any semester. This limit appears as part of the input data. The third example below illustrates this issue.  Input  There are one to twenty-five data sets, followed by a final line containing only the integers -1 -1. A data set starts with a line containing two positive integers n, 1 <= n <= 12, which is the number of courses in this data set and m, 2 <= m <= 6, which is the maximum number of courses that can be taken in any single semester. The next line contains the n course identifiers. Each is a 1-5 character string from the set {a-z, 0-9}. Following the course identifiers is the individual course information. This consists of n lines, one line for each course, containing the course identifier, semester offered ('F'=Fall, 'S'=Spring, 'B'=Both semesters), the number of prerequisite courses, p, 0 <= p <= 5, and finally p prerequisite course identifiers. The first example data set below corresponds to the problem described above.  Output  The output contains one line for each data set, formatted as shown in the sample output.  Sample Input  4 6 cs123 mt42 cs456 cs789 mt42 F 0 cs123 S 0 cs456 S 2 cs123 mt42 cs789 B 1 cs456 3 6 math1 comp2 comp3 comp3 S 1 comp2 math1 S 0 comp2 F 1 math1 4 3 m10 m20 c33 c44 m10 B 0 m20 B 0 c33 B 0 c44 B 0 -1 -1 Sample Output  The minimum number of semesters required to graduate is 5. The minimum number of semesters required to graduate is 4. The minimum number of semesters required to graduate is 2.

algorithm					Design and implement LRU Cache.

algorithm					Array = {5, 2, 1}     circular rotate array,  calculate sum by multiplying each array elements with index and find minimum sum from all of rotated arrays.    Time Complexity should be O(n)          5x index + 2 x index + 1xindex  = Sum     Step 1:     5x1 + 2x2 + 1x3    =    5+4+3 ==>  12    Step 2: (rotate array)  {2,1,5}                  2x1 + 1x2 + 5x3   = 2+2+15  ==>   19    Step 3:   (rotate array) { 1,5, 2}                 1x1 + 5x2 + 2x3 = 1+10+ 6 ==>  17   Step 4:  (rotate array)  {5,2,1}  same as input array stop and print minimum sum  1.e  12

algorithm					Given a string left rotate it by given number of times with O(n) solution

algorithm					Given a array where each element is maximum +-k index away from it's sorted position, find an algorithm to sort such array.

algorithm					Say you have a keypad that has keys for the numbers 0 through 9 and the correct code is some sequence of 5 digits. This keypad does *not* reset after entering an incorrect sequence of 5 digits. ie. If the correct sequence is 12345, entering 7512345 will succeed in opening it because it ends in the correct sequence. If the keypad actually resets after every 5 digits pressed, then it would not succeed b/c it would interpret the above sequence as "75123" then "45".  1. Write an algorithm that will try to find the correct code for this keypad. Assume you have an API similar to KeyPad.pressKey(int n) where you pass in a number (0...9) and it returns true if the keypad unlocks and false if it's still locked.  Note that you could easily enter all digits of all numbers 00000 through 99999 resulting in 5*100000 key presses, but remember that the panel does not reset after every sequence of 5 digits, so find a way to do this more efficiently. Notice for example that entering the stream 3791283780 will test the length 5 sequences 37912, 79128, 91283, 12837, 28378, 83780; not only the two disjoint sequences 37912 and 83780.  Think of this keypad as remembering the last 4 keys pressed (and the order pressed); when the next key is pressed, if the last 4 keys + the current key equal the correct code, the keypad will unlock. Assume the keypad does all this internally, so you can just keep feeding it keypresses and it will eventually unlock if the last 5 keypresses entered is the correct code.  2. Generalize your algorithm to work for a keypad where you don't know the length of the correct sequence in advance.

algorithm					In the game of Jack Straws, a number of plastic or wooden "straws" are dumped on the table and players try to remove them one-by-one without disturbing the other straws. In the question here, we are concerned with the following, related problem: First n straws are dumped on the table. Next, for every pair of straws, we want to determine if the straws are connected by a path of touching straws. In other words, given a list of the endpoints for n > 1 straws (as if they were dumped on a large piece of graph paper), determine all the pairs of straws that are connected. Note that touching is connecting, but also two straws can be connected indirectly via other connected straws. Give an algorithm to compute all the pairs of straws that are connected. Here is some additional information that you can use:   As a basic step you need to determine whether two straws directly touch (intersect), i.e., whether straw ab with end points a and b intersects with straw cd (with end points c and d). To get full credit also explain how the elementary step i) can be done. If you cannot find an algorithm for this step, assume an O(n 2 ) algorithm and explain how to find all pairs of straws that are connected. Analyse and explain the worst-case computational complexity of your algorithm in terms of n.

algorithm					Given a lane where there are various houses each containing a fixed amount of gold. Now a robber has to rob the houses such that when he robs a house the adjacent one cannot be robbed.Calculate the maximum amount of gold collected by him.

algorithm					Given a review paragraph and keywords, find minimum length snippet from paragraph which contains all keywords in any order.

algorithm					Given the array of integers containing equal number of even and odd numbers. Rearrange the array such that even number is at even place and odd number is at odd place. Example : [2,1,3,4,7,9,24,98] Answer : 1,2,3,4,7,24,9,98

algorithm					Implement cycle detection for a spreadsheet with the characteristics outline below.  Your solution should include working data structures to represent the spreadsheet and operate on a "entire" spreadsheet to indicate which cells have circular dependencies.  Spreadsheet  The spreadsheet is a collection of cells within a 2-D space of columns and rows.  Columns are defined with a letter and rows are defined by a number.  You can assume an upper limit of 26 columns for simplicity.  Cell values are either a number (long or double) or an expression containing numbers, operators, and references to other cells (i.e. B2 means the second column [B] and second row [2]).  You can ignore the parsing of expressions for this exercise.  Instead, your solution can define the data you will work with after expressions have been parsed.  Cycles  A cycle occurs when a cell refers to itself either directly or indirectly via an expression.

algorithm					Given an array of integer nos. All numbers are distinct. WAP to find the two longest non-intersecting continuous subarrays  of equal size s.t. *all* elements of one of them are smaller than that of the other subarray:  a[i..i + k - 1] and a[j..j+k-1] where i + k <= j s.t. a[i..i + k - 1] < a[j..j+k-1] or a[i..i + k - 1] > a[j..j+k-1] and k is maximal  Example: a = {1,2,3, 7, 9, 8} then we have: {1, 2, 3} and {7, 9, 8} a = {6, 5, 4, 1, 3, 7} then we have:  {6, 5} and {4, 1} or  {6, 5} and {1, 3} or  {5, 4} and {1, 3} ...

algorithm					Given a big rectangular plot of land that has rectangular or square sized buildings (all sides of every building are parallel to the big rectangular plot)... find the location and dimensions of the largest square that can be built in this rectangular plot

algorithm					Given an bunch of airline tickets with [from, to], for example [MUC, LHR], [CDG, MUC], [SFO, SJC], [LHR, SFO], please reconstruct the itinerary in order,  for example: [ CDG, MUC, LHR, SFO, SJC ]. //tickets can be represented as nodes

algorithm					Given a list of queries and their counts, write a function that returns one of the queries at random such that over time it returns an equal distribution based on the counts provided in the input.

algorithm					Given an array of integers and a number. WAP to find the pairs which sum of upto given number.  I solved it. Then he asked about writing test cases for this function.  I wrote below test cases  1.) All the elements should be number. 2.) Length of array should not be 0. 3.) Array itself should not be null. 4.) Given number, arrayLength can be represented by 32bits or 64 bits. 5.) number should not be negative. 6.) Input does not has pair, It should return false 7.) Input has pair, It should return true 8.) Input has all negative values and pair exists, then function should return true 9.) Input has all negative values and pair does not exists, function should return false  He told that he is looking for more test cases. Can you guys think of some more complex test cases.

algorithm					You are given a list of word. Find if two words can be joined to-gather to form a palindrome. eg Consider a list {bat, tab, cat} Then bat and tab can be joined to gather to form a palindrome.   Expecting a O(nk) solution where n = number of works and k is length  There can be multiple pairs

algorithm					You are given a catalog of books, which have following attributes :-  Name, Author, Publisher, Publish year, Category, Price, Count (sold)  Implement following APIs on top of this catalog -  1) addBookToCatalog(Book) 2) searchBook(by partial book name/author)  3) getMostSoldBooks(by author name/category, limit)  Expectations: Maintain DB on memory  Code should be readable. Design, handle naming convention,handle exceptions & should be running

algorithm					You have to compress a string in the following format. eg 1- : input : aasasatb output : 2a2sa1t1b eg2  -: input: abcdbcdff output :- 1a2bcd2f

algorithm					write a merge sort algorithm to sort a file which can't be loaded into the memory. Assume you can only load 10 items in the memory at a time and there are 100 items to sort.

algorithm					0 1 ? ? wildcard for 0 or 1  "01?" 010 011  Example: 01?0? Will produce 01000 01100 01001 01101

algorithm					We know a string is Palindrome if it is the same reading from both sides. Now we define the following string also Palindrome:  A man, a plan, a canal, Panama!  Write a code that returns if an string is palindrome and  it should return true for above input. (Without directly saying, I should conclude that I have to only consider alphanumerical characters in a string). In addition, we assume the string is very long and we can not keep a copy of this string or even a copy of preprocessed version of this string. Therefore the result should be returned with the first sweep of the string.

algorithm					there are 1 billion stars and you are standing at the earth. From the earth , you know the distance of all 1billion stars. Find the nearest 1 million stars from the earth.

algorithm					There are discounts on particular time period suppost Day1 - Day5 => 10% Day2 - Day 8 => 5% Day4 - Day6 => 20 %  find the period where maximum discounts is available.  For above example the period is Day4 - Day5 => 10+5+20   that means 35%  Provide the generalize solution. Period can be time also.

algorithm					write a function:

algorithm					Find and fix the bugs in the following function that is supposed to remove the head element from a singly linked list.   void RemoveHead (node * head) {     free(head);     head = head - > next; }

algorithm					Write a function that takes a string as an input and outputs an integer, e.g. turning "1234" into 1234.

algorithm					Given a String find the first non repeating char in a single pass of the string. Assume a big character set like utf-8 (eleminate use of char[256]) Avoid any subloop to have a very optimal solution

algorithm					you have a interface called Op and a Filter interface interface Op<T> {     public boolean hasNext();     public boolean<T> next(); }  interface Filter<T1, T2> {     public boolean filter(T1 t1, T2 t2); }  design a MutualOp that has below API, MutualOp should return the ops that combine op1 and op2, also should meet with the filter  class MutualOp implements Op{     public MutualOp(Op left, Op right, Filter<Op, Op> filter) {         this.left = left;         this.right = right;         this.filter = filter;     }      public boolean hasNext {         ......     }      public T next {         ......     } }

algorithm					Assuming you're playing one game that you need guess a word  from a dictionary. You're given a machine you can try to guess the word, the machine will return how many characters has been matched by your guess. Design a system to crack the word.

algorithm					Permutate a list of string  this question is supposed permutate the characters instead of who string,   as input example {"red", "fox", "super" }, the expected output is  rfs rfu rfp rfe rfr ros rou rop roe ror rxs rxu rxp rxe rxr efs efu efp efe efr eos eou eop eoe eor exs exu exp exe exr dfs dfu dfp dfe dfr dos dou dop doe dor dxs dxu dxp dxe dxr

algorithm					A 2D array filled with integer, define a flow from one point to its neighbor only if the value of current point is not less than its neighbor's value. Consider up edge and left edge as east coast, bottom edge and right edge as west coast, find all position that it can flow to east coast and west cost both

algorithm					Let's assume that there's an array that has nonzero natural numbers where all the numbers repeat an even number of times, except for one value that repeats an odd number of times.  Can you write me a function that takes this array, and returns the value that occurs the odd number of times?  Ex : - [ 4, 7, 2, 2, 5, 3, 5, 7, 7, 3, 4, 5 ]

algorithm					/* For each node in a binary tree find the next right node on the same depth. Write a function that takes root node and populates "next" with the answer for each node.         A      /   \     B ->  C    /     / \   D ->  F-> G  /       \ H   ->    I  class Node {   Node left;   Node right;   Node next; // <-- answer should be stored here };  B.next = C D.next = F F.next = G H.next = I {A, C, G, I}.next = null */

algorithm					Given an array of numbers, find a pair whose sum is closest to zero.

algorithm					Given a dictionary that contains mapping of employee and his/her manager like this        Dictionary<string, string> employees = new Dictionary<string, string>()             {                 { "A","C" },                 { "B","C" },                 { "C","F" },                 { "D","E" },                 { "E","F" },                 { "F","F" }             };  Write a function to get no of employees under each manager in the hierarchy not just their direct reports. In the above dictionary the root node/ceo is listed as reporting to himself.  Output should be a Dictionary<string,int> that contains this      A - 0     B - 0     C - 2     D - 0     E - 1     F - 5

algorithm					N queen problem.  In NXN chess board, you have to arrange N queens such that they do not interfere each other. Following is how you define interference of queens. 1. Two queens cannot be on the same diagonal 2. Two queens cannot be in same horizontal or vertical line 3. Queen can jump like a knight. So, two queens cannot be at a position where they can jump two and half steps like a knight and reach the other queen.  You should return the possible ways to arrange N queens on a chess board.  This was a tech screen, but since I was local, they called me in their office rather than phone interview.   Hint: Don't try too hard, the best solution is n!

algorithm					public interface Triangle {         /**       * Three segments of lengths A, B, C form a triangle iff       *       *      A + B > C       *      B + C > A       *      A + C > B       *       * e.g.       *  6, 4, 5 can form a triangle       * 10, 2, 7 can't       *       * Given a list of segments lengths algorithm should find at least one triplet of segments that form a triangle (if any).       *       * Method should return an array of either:       * - 3 elements: segments that form a triangle (i.e. satisfy the condition above)       * - empty array if there are no such segments       */      int[] getTriangleSides(int[] segments);  }

algorithm					Given an array such that every next element differs from the previous by +/- 1. (i.e. a[i+1] = a[i] +/-1 ) Find the local max OR min in O(1) time. The interviewer mentioned one more condition that the min or max should be non-edge elements of the array Example: 1 2 3 4 5 4 3 2 1 -> Local max is 5 1 2 3 4 5 -> No local max or min exists 5 4 3 2 1 -> No local max or min exists

algorithm					Given an array of int return the maximum difference of any pair of numbers such that larger number of the pair occurs at higher index than the smaller.

algorithm					Graph problem: Critical node: If a node reaches another node only through one node. Eg: A-C-B and A-E-B are critical nodes. (A reach B through one node which is C or E) If A reaches B through more than one node, then they are not critical nodes. 1) A-C-B A-D-E-B (A reach B thro C which might lead to critical node but A has another path to B thro D and E, so they are not critical nodes). 2) X-Y-Z X-A-Z (X and Z are critical nodes) Now find all critical nodes.

algorithm					Given an unsorted array of natural numbers. Where numbers repeat in array. Out put numbers in the order of frequency. Where number of out put is passed as parameter. For Ex: Array -> [0, 0, 100, 3, 5, 4, 6, 4, 2, 100, 2, 100] n -> 2 Out put -> [100, 0] or [100, 2] Since 100 is repeated 3 times and 0, 2 is repeated 2 times, out put up to 2 most frequent elements, program should out put either 100, 0 or 100, 2

algorithm					write a function that detects conflicts in given meeting schedules input: a list of intervals, [(s1, e1), (s2, e2), ] output: return True if there's any conflict, False otherwise

algorithm					You are given printouts from an algorithm which ran over an unsorted binary tree. One printout is from an in-order run and another from a pre-order run. Can you reconstruct the tree? If so, then write an algorithm.

algorithm					You are given printouts from an algorithm which ran over a sorted binary tree. One printout is from an in-order run and another from a pre-order run. Can you reconstruct the tree? If so, then write an algorithm.

algorithm					You have N points on a 2D surface. List K points at a shortest distance to the point (0, 0).

algorithm					Assume we only take the least significant digit of each value in fibonacci sequence, and form the sequence of digits into pairs. In those pairs, the first value of one pair is the same as second value of its predecessor.  As we know the fibonacci sequence is 1, 1, 2, 3, 5, 8, 13, 21...  so the pair sequence is: [1, 1], [1, 2], [2, 3], [3, 5], [5, 8], [8, 3], [3, 1] ...  Write a function to output the first n pairs of this sequence. void Outputpairs(int n)

algorithm					You are given two strings. String T is a string where characters need to be reordered. String O contains characters (none of them repeated) which defines the order/precendence to be used while reordering the string T. Write an algorithm to do the reordering.  *** SPOILER ALERT ***  The question was pusposefully underspecified - upon questioning it was revealed that the string O might not necessarily include all characters used in string T - the characters not included in string O are supposed to be placed at the beginning of the resulting string (in no particular order).

algorithm					You are given two arrays - A & B. The length of the arrays is the same - N. The values in the arrays are integers from 0 to N - 1 in random order and no number is repeated. You need to list a sequence of two-element swaps required to reorder the array A into the order of the array B. Additionally, at each step of the sequence you are allowed to swap two elements only if one of them is 0.

algorithm					Given a Integer, find the maximum number that can be formed from the digits. Input : 8754365 output : 8765543  I told solution in nlogn. He asked me optimize further.

algorithm					Write a method that takes the root of a tree as input and check if the tree is a Binary Search Tree (BST).

algorithm					given an expression like 3*4 + 8-9 (only +, - , * operators) as a string evaluate it strictly from left to right

algorithm					Check if the given binary tree is a unival tree. (all nodes have same value)  Follow up- Count the number of unival subtrees in a binary tree.

algorithm					You are given a function: List<TimeSlot> getTimeSlots (String friend) Assume getTimeSlots() returns available times for a friend, sorted in order, with no overlap. Assume TimeSlot has comparable function   You want to schedule a meeting among all of your friends, such that all can attend.  Implement a function to get the first 3 common TimeSlots among all your friends: List<TimeSlot> get3CommonTimeSlots (List<String> friends)  user1 1-2pm, 3-4pm, 7-8pm user2 1-2pm, 5-6pm

algorithm					You are tasked with implementing a method that returns the lowest possible number that could be generated after removing n characters from a string of digits. The method signature should look like:

algorithm					You are given a 2d rectangular array of positive integers representing the height map of a continent. The "Pacific ocean" touches the left and top edges of the array and the "Atlantic ocean" touches the right and bottom edges.    - Find the "continental divide". That is, the list of grid points where water can flow either to the Pacific or the Atlantic.  Water can only flow from a cell to another one with height equal or lower.   Example:   Pacific ~ ~ ~ ~ ~ |__   ~  1  2  2  3 (5) ~   ~  3  2  3 (4)(4) ~   ~  2  4 (5) 3  1  ~   ~ (6)(7) 1  4  5  ~  __ (5) 1  1  2  4  ~    |~ ~ ~ ~ ~ Atlantic   The answer would be the list containing the coordinates of all circled cells:  [(4,0), (3,1), (4,1), (2,2), (0,3), (1,3), (0,4)]

algorithm					Problem Statement  Diameter  The diameter of a graph is the maximum shortest path between any two nodes.  At the beginning, there is a simple grpah contains exactly 1 node. Then we add new nodes one by one to the graph. Each time when we add a new node to the graph, we also add exactly one edge to connect this node to another node which already exists.  We want to find the diameter of the graph each time we add a new node. Note that each edge cost 1.  Input Format:  First line of the input contains one integer N, indicating how many new nodes we will add.  Then following N lines. The ith line contains an integer X, which means we add the ith node and an edge connecting the Xth node and ith node.  The original node is the 0th node.  Output Format:  Output N lines. The ith line is an integer indicating the diameter of the graph after adding the ith node.  Constraints:  0 < N <= 100000  0 <= Xi < i  i is counting from 1  Sample Input:  5  0  0  1  1  1  Sample Output:  1  2  3  3  3  Explanation:  Firstly the graph contains only node 0. The first line of output is 1 because the diameter becomes 1 when node 1 is added and connected to node 0. Diameter becomes 2 after adding node 2 to node 0. Then adding node 3, 4, 5, all of them are connecting to node 1, caculate the shortest path of all pairs of nodes, the maximum shortest path is 3, so the last 3 lines of output are all 3.

algorithm					You are given a class name Person that looks like this

algorithm					Write a function that takes an integer as input and produces an output string.  Some sample Input/outputs are as follows  i/p o/p 1 - A          2 - B 3 - AA 4 - AB 5 - BA 6 - BB 7 - AAA 8 - AAB 9 - ABA 10 - ABB 11 - BAA 12 - BAB 13 - BBA 14 - BBB 15 - AAAA

algorithm					A robot has to move in a grid which is in the form of a matrix. It can go to  1.) A(i,j)--> A(i+j,j) (Down) 2.) A(i,j)--> A(i,i+j) (Right)  Given it starts at (1,1) and it has to go to A(m,n), find the minimum number of STEPS it has to take to get to (m,n) and write public static int minSteps(int m,int n)   For instance to go from (1,1) to m=3 and n=2 it has to take (1, 1) -> (1, 2) -> (3, 2) i.e. 2 steps

algorithm					Consider a social network graph like facebook. You are throwing a party and want to invite some of your friends. Design a algorithm to select top n friends from m friends using the social graph.

algorithm					Given an m x n matrix where each row element is sorted, but the columns do not appear in sorted order, write a function to print each matrix element in sorted order.  Example matrix: matrix = [ 	[20, 40, 80], 	[5, 60, 90], 	[45, 50, 55] ]  Your function should print 5, 20, 40, 45, 50, 55, 60, 80, 90.  Add on: Assume that we are space-constrained such that we can only hold one row in memory at a time. Optimize your function to work under such constraints as efficiently as possible.

algorithm					Given a matrix of integers where each row is sorted but the columns are not sorted, print each matrix element in sorted order.   Here's an example matrix:

algorithm					Question: Given two strings, find number of discontinuous matches.  Example: cat, catapult  Output: 3   => CATapult, CatApulT, CAtapulT

algorithm					You have a function rand5(). This function returns numbers between 1 and 5 randomly with equal probability. Implement a function rand7() which makes use of rand5 to return a number between 1 and 7 randomly with equal probability.

algorithm					Question:  Given a sequence of positive integers A and an integer T, return whether there is a continuous sequence of A that sums up to exactly T Example [23, 5, 4, 7, 2, 11], 20. Return True because 7 + 2 + 11 = 20  [1, 3, 5, 23, 2], 8. Return True  because 3 + 5 = 8 [1, 3, 5, 23, 2], 7 Return False because no sequence in this array adds up to 7

algorithm					Find popular item in sorted array of natural numbers. An item is popular is if its repeated n/4 times or more. For Ex: Input: 123444445678 Popular item is 4.  Liner scan is O(n), but solution needs to be in O(logN) complexity and O(1) space complexity.

algorithm					given a string without space "iamstudent" output "i am student" u are provided with a dictionary to check words

algorithm					A plumber working for a company as a contractor. His job is attend services and submit the bill to get his salary on basis of daily work including his service charge 500 rupees. For a typical plumbing work he need pipes with different lengths. But in market he will get new pipe with standard size 100m of cost 100 rupees. (no small or large sized pipes available) Now , he need 10 , 40 , 60, 70 lengths of pipes for a jobwork.    Generally company  gives him (4 pipes * 100 rupees) + 500rupees as service charge = 900 rupees. but plumber bought only 2 pipes cut as follows and get his job done... 1st pipe => 40+60 2nd pipe => 10+70 + extra left(20) By buying only 2 pipes he get his job done. remaining 2 pipes money saved.  write an efficient algorithm to calculate minimum number of standard size pipes required for given number of different pipes lengths:  Input: N => total pipes for jobwork arr[N] => lengths of pipes. (for simplicity, pipe size will be either smaller or equal to standard size)  outpud:  minimum statdard sized(100m) pipes required  constraint: you can only cut them can not join them back as follows say he need 10 95 95,  with two pipes 100 100 = > 95+5 95+5 => 95 95 (5+5)// this is not accepted  EX:  Input: 5 20 30 50 60 80  output: 3  Input: 5 10 10 10 15 20 35 55 60 70 75 75 80  output: 6

algorithm					Which is best Merge Sort or QuickSort?  Why and How?

algorithm					Amazon wants to implement a new backup system, in which files are stored into data tapes. This new system must follow the following 2 rules:   1. Never place more than two files on the same tape.   2. Files cannot be split across multiple tapes.   It's guaranteed that all tapes have the same size and that they will always be able to store the largest file.   Every time this process is executed, we already know the size of each file, and the capacity of the tapes. Having that in mind, we want to design a system that is able to count how many tapes will be required to store the backup in the most efficient way.   The parameter of your function will be a structure that will contain the file sizes and the capacity of the tapes. You must return the minimum amount of tapes required to store the files. Example: Input: Tape Size = 100; Files: 70, 10, 20 Output: 2

algorithm					Given a list of employees and their bosses as a text file   , write a function that will print out a hierarchy tree of the employees.    Sample input =  Sam, Ian, technical lead, 2009 / Ian, NULL, CEO,2007/ Fred, Sam, developer, 2010  The format is name, supervisor, designation, year of joining  The output should be   Ian CEO 2007 -Sam Technical lead 2009 - -Fred Developer 2010

algorithm					You are given a set of unique characters and a string.  Find the smallest substring of the string containing all the characters in the set.  ex: Set : [a, b, c] String : "abbcbcba"  Result: "cba"

algorithm					write an algorithm to find sum of numbers which are smaller than N and divisible by 3 or 5  Example: N = 9 => 3 + 5 + 6 = 14 N = 10 => 3 + 5 + 6 + 9 = 23

algorithm					design and implement a calculater that can calculate expressions like: + 2 4  * 8 ( + 7 12) ( + 7 ( * 8 12 ) ( * 2 (+ 9 4) 7 ) 3 )  (PS:all items are space delimetered.)  Example answers + 2 4 => 2 + 4 = 6 * 8 ( + 7 12) => 8 * ( 7 + 12 ) = 152 ( + 7 ( * 8 12 ) ( * 2 (+ 9 4) 7 ) 3 ) => 7+8*12+2*(9+4)*7+3 = 148

algorithm					there are numbers in between 0-9999999999 (10-digits) which are assigened someone (does not matter which number assigned who)  Write two methods called "getNumber" and "requestNumber" as follows Number getNumber(); boolean requestNumber(Number number);  getNumber method should find out a number that did not assigened than marks it as assiged and  return that number.  requestNumber method checks the number is assigened or not. If it is assigened returns false, else marks it as assiged and return true.  design a data sturucture to keep those numbers and implement those methods

algorithm					{{ There are 3 machines M1, M2 and M3. Each machine is 90% full of its capacity with integers. Now you have to sort all the integers combined and then store the first 1/3rd in M1, second 1/3rd in M2 and last 1/3rd in M3.   Your objective is to minimize the number of sort operations and number of data transfer operations. Each sort operation/data transfer operation is counted as 1 irrespective of the count of values that are being sorted/transferred.  }}

algorithm					How to find efficiently the minimum of an array of integers that is the maximum of other arrays?  Example: A = [126, 110, 130] B = [125] C = [105, 115]  The minimum element of array A that is the maximum of B and C is 126

algorithm					Write a function that receives a stream of pairs: id (some unique integer) + weight (positive real number). The stream ends with the special pair {0,0}. The function should return one the unique ids at random, with probability proportional to its weight (compared to the total weights sum when stream has ended). Stream size and weights sum are unknown in advance, and you are allowed O(1) memory consumption.  Example: If this was the stream: {1,2},{2,2},{3,4},{4,10}, then id 2 would be returned with probability 1/9.

algorithm					Write a class that receives in the constructor a vector of strings representing a browser history (URLs), and a method for "auto-complete": The method that receives a string representing a partial URL typed by the user and returns a vector of all possible completions of this partial URL (prefix).

algorithm					You have a binary search tree and you have to return the two nodes such that there sum i equal to K. Pseudo code is to be given.  O(n)time & O(n) sppace is easy but challenge O(n) time & O(1) space.

algorithm					You are given a 2D Array that contains only 0s and 1s in sorted order. i.e. First Os and then 1s.  Array: 0 0 0 1 1 1 1 1 0 0 1 1 0 1 1 1  You have to figure out the row that contains maximum number of 1s.  e.g. in above case we have row 2 as the answer.

algorithm					Given two sorted arrays, mergesort them into 2nd array that has enough space to accommodate both.

algorithm					Given row on N house, each is marked either R or B. And each house having some gems. You have to collect gems from these house with some constraint: You can choose gems from any blue house but you have to choose even number of red house ( either from 2 Red houses or from 4 red houses) each time you take gem from one house, you will multiply gems received with gems currently, you have.  You have to choose continuous houses. You have to return start point and end point of house (remember this should be continuous )

algorithm					you have given array of Size N and two numbers M, K. K is size of subarray and M is count of subarray. You have to return sum of max M subarray of size K (non-overlapping)  N = 7, M = 3 , K = 1   A={2 10 7 18 5 33 0} = 61  subsets are: 33, 18, 10 (top M of size K)   M=2,K=2  {3,2,100,1} = 106 - subsets are: (3,2), (100,1) 2 subsets of size 2

algorithm					Design a data structure for following operations in O(1) time.: insert remove (FIFO) find MODE

algorithm					Given an array of integers find the element for which the sum of left = sum of right. example -1 100 1 98 1 should return index of 1 i.e 2   Answer: First told him about Brute Force approach and then told him if we can iterate once and get the total sum

algorithm					Inplace reverse a sentence  You given a sentence of english words and spaces between them.  Nothing crazy: 1) no double spaces 2) no empty words 3) no spaces at the ends of a sentence

algorithm					The closest common ancestor in a tree forest.

algorithm					3> write program to find wrong no of "(()" parenthesis in expression "((B+a)"          give error for "((A))" - for unnecessary brackets

algorithm					1> write program to calculate power(x,n) in log(n) time

algorithm					Given a 4 X 4 game slot that has random alphabets in all the slots Write a function that takes the keyboard and the word as input and returns true if the word can be formed False otherwise.  A word can be formed on the board by connecting alphabets adjacent to each other (horizontal, vertical and diagonally)  Same alphabet should not be reused.

algorithm					Design a TinyURL like Service.

algorithm					You have String array like{'cat','good','tac','act''....} like some 1000 words. So if i give input tac ,output should be cat and act.. How can we implement with less complexity

algorithm					Given an array of integers, return true if there're 3 numbers adding up to zero (repetitions are allowed) {10, -2, -1, 3} -> true {10, -2, 1} -> true -2 + 1 +1 =0

algorithm					Print all subset of a given set which sums up to ZERO {8,3,5,1,-4,-8} so ans will be : {8,-8}                         {3,5,-8}                         {3,1,-4}  size of set can be upto 50 but elemet of set can be as big as 18 digit number

algorithm					Given a binary search tree (BST), write a mehtod that will convert this BST into a doubly linked list that is sorted (ascending or descending order) and returns the first element in this list.  You may assume you are given following Node class:

algorithm					Given a Tree:

algorithm					boolean checkPattern(String str) { // Implementation }  Implement the method checkPattern. str is a string argument. Return true: if the string is following any pattern example: xyzxyzxyz Here "xyz" is the pattern  return false: String is not following pattern example: xyzxyzA A is not in part of pattern.

algorithm					Design and Implement a Telephone database structure in which a Customer Entry has PhoneNum,Name,Address.   a) Given any PhoneNum return all the Customer details b) Given any Name list all the Entries (As Name can be duplicate, only PhoneNum is unique) c) Also Name searching should support Prefix Based.

algorithm					Given an array of ages (integers) sorted lowest to highest, output the number of occurrences for each age. For instance:  [8,8,8,9,9,11,15,16,16,16] should output something like: 8: 3 9: 2 11: 1 15: 1 16: 3  This should be done in less than O(n).

algorithm					Constructing Bridges: A River that cuts through a set of cities above and below it. Each city above the river is matched with a city below the river. Construct as many Non-Crossing Bridges as possible. Input: Above Bank >> 7 4 3 6 2 1 5 Below Bank >> 5 3 2 4 6 1 7 are given in pairs: (7,5) (4,3) (3,2) (6,4) (2,6) (1,1) (5,7) Output: (1,1) (3,2) (4,3) (6,4) (7,5)

algorithm					You are given a file which contains 3 values - start time, end time, amount of water flowing between the start time and end time for one day  The start time and end time may overlap and are inclusive. The times are not in a sorted order  Example: 0,10,100 10,15,300 16,20,400 5,15,200  Find the max flow of water at any instant of time. In the above example, the answer is 600 ( at instant 10)

algorithm					Print a BST such that it looks like a tree (with new lines and indentation, the way we see it in algorithms books).

algorithm					Write a function that takes the following inputs and gives the following outputs.  Input: A list of points in 2-dimensional space, and an integer k Output: The k input points closest to (5, 5), using Euclidean distance   Example:  Input: {(-2, -4), (0, 0), (10, 15), (5, 6), (7, 8), (-10, -30)}, k = 2 Output: {(5, 6), (7, 8)}

algorithm					given a vector of integers, v[i] represent the stock price on day i. Now you may do at most K transactions. you must sell your stock before you buy it again and that means you can NOT have two stocks at the same time. write a program to find max profit you can get.

algorithm					Given a staircase that has 'n' step, and you climb the staircase by jumping over the steps. You can cover at max of 'k' steps in a single jump. List all the possible sequence of jumps you could take to climb the staircase.  input:  n=4, k=2  output: 1,1,1,1 1,1,2 1,2,1 2,1,1 2,2

algorithm					Given a list of strings, return a list of lists of strings that groups all anagrams.  Ex. 	given {trees, bike, cars, steer, arcs} 	return { {cars, arcs}, {bike}, {trees, steer} }  m = # of words n = length of longest word  I solved this in O(m * n * log n) time.

algorithm					You have a chess board of size NxN. You have a horse at a given starting position. You also have a function that gives you all the positions that the horse can reach from it's current position.   Given an ending position, find the path to it that uses the minimum number of moves.

algorithm					Given two input string check if anyone is substring of other.  example aaaaaabbb, aaaabbb return true  PS: Don't use any internal string library :)

algorithm					Given an integer array, adjust each integers so that the difference of every adjcent integers are not greater than a given number target.  If the array before adjustment is A, the array after adjustment is B, you should minimize the sum of |A[i]-B[i]|    You can assume each number in the array is a positive integer and not greater than 100   Given [1,4,2,3] and target=1, one of the solutions is [2,3,2,3], the adjustment cost is 2 and it's minimal. Return 2.

algorithm					Give you a list of Modules of Dependencies,  A --> B,C B --> D,E,F D --> F And please return back a correct build order of Module (input)

algorithm					Give an 2d-characters Grid, char[][] A, and a dictionary, List<String> dict. Search all possible words in the 2d-Grid.

algorithm					Take a list of integers (left to right order) and return an integer of the number of identical binary trees that can be created from the same list.  Input:    [10, 8, 15, 6, 9, 4, 5] Output: 24  Input:    [12, 6, 19, 15, 5] Output: 6  Input:    [44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64] Output: 1  I wrote a brute-force 'solution', creating a binary tree for each permutation of the list (with the same root as Input list) and compared each to the binary tree from the Input list. For large input lists (length > 10), my 'solution' is useless.

algorithm					Given a set of busy time intervals of two people as in a calendar, find the free time intervals of both the people so as to arrange a new meeting input: increasing sequence of pair of numbers per1: (1,5) (10, 14) (19,20) (27,30) per2: (3,5) (12,15) (18, 21) (23, 24) ouput: (6,9) (16,17) (22,22) (25,26)

algorithm					Given an array of integers.  Move all non-zero elements to the left of all zero elements.

algorithm					There's a new language which uses the latin alphabet. However, you don't know the order among letters.  It could be: a b c d ...  as it could also be:  b e z a m i ...  You receive a list of words lexicographically sorted by the rules of this new language. From this list, derive one valid particular ordering of letters in this language.

algorithm					There are different buildings standing close to each other. These are of same width but different height. Suppose if rainfall happens, what will be the volume of  water that get trapped on top of all these buildings together. ?  INPUT (Example)  No: of buildings : 4 heights of the buildings(in any units): 3 4 3 4

algorithm					Given a array of positive integers, find all possible triangle triplets that can be formed from this array.  eg: 9 8 10 7  ans: 9 8 10, 9 8 7, 9 10 7, 7 8 10 Note : array not sorted, there is no limit on the array length

algorithm					Given an array of type:- 1. Increasing 2. Decreasing. 3. Increase-Decrease 4. Decrease-Increase  Find:- 1. Type of array in minimum steps ? 2. Maximum element from array in min steps?

algorithm					Question was "Given a pattern and a string input - find if the string follows the same pattern and return 0 or 1. Examples: 1) Pattern : "abba", input: "redbluebluered" should return 1. 2) Pattern: "aaaa", input: "asdasdasdasd" should return 1. 3) Pattern: "aabb", input: "xyzabcxzyabc" should return 0.   I can think of a brute-force solution for this question where we add the character in the pattern and n length of the string to a hashmap and recurse over the pattern array and string. But is there anything more efficient? This was a pretty difficult question in my opinion.

algorithm					There are multiple rooms in a floor. There are one or more fire exits. Each door can be designed with an option of pull or push. For fire safety, a door should be designed so as to open (push) towards the fire exit.  Design a data structure to represent the floor and door design.  A person could start from any room and moves towards fire exit. Write an algorithm to check if all the doors are designed to be pushed towards fire exit.

algorithm					Given a large array of unsigned ints, quickly find two who's sum is 10  Then the interviewer asked me to write test cases.  Followed by how to implement this on a distributed system, where multiple systems can read/write simultaneously on a shared cache (HINT: It is ok if you do not return the first instance)

algorithm					There is a string whose characters can only be either a, b or _ (there can be only one _ in the string). At each step, we can modify the string as follows: 1. _ can be swapped with its adjacent character, example a_ba can be changed to either _aba or ab_a. 2. Two characters adjacent to _ (both on the same side of _) can be reversed along with the _ if both characters are different, example, aa_ba can be changed to aaab_ but not to _aaba because both characters are a. You are given two strings, the initial state and the final state (lengths will be same), you have to output the minimum number of steps required to change the string in initial state to the string in the final state. example: input: a_b ab_ output: 1 input: abaa_a b_aaaa output: 4 reason for example 2:- abaa_a -> aba_aa -> ab_aaa -> _baaaa -> b_aaaa

algorithm					You have a sorted array containing the age of every person on Earth.  [0, 0, 0, 0, ..., 1, 1, ..., 28, 28, ..., 110, ...]  Find out how many people have each age.

algorithm					Write a program to find pattern.  0: 1 1: 11 2: 21 3: 1211 4: 111221 5:  312211  Iterate over the previous number, and find count for same number number.  Append that count before number.  e.g.,   public String pattern(int input){}   If input = 4, function should return 111221.

algorithm					Minesweeper question: Given an n x m grid holding individual mine co-ordinates, identify all of the mine clusters. A mine cluster is the largest collection of neighboring mines.  Example input:   0 1 2 3 --------- 0|0|1|0|1 1|0|0|1|1 2|0|0|0|0 3|1|1|0|0  Expected output:  [cluster 1] (0,1),(1,2),(1,3),(0,3) [cluster 2] (3,0),(3,1)

algorithm					Let's say there is a double square number X, which can be expressed as the sum of two perfect squares, for example, 10 is double square because 10 = 3^2 + 1^2  Determine the number of ways which it can be written as the sum of two squares

algorithm					Sort the elements inside a stack using only push and pop opperation. Is it possible to do it only with one additional stack?

algorithm					given a range of number 1 through N, where N >=3. you have  to take an array of length 2N and place each number ( from the range 1 to N) twice. such a that the distance between two indexes of a number is equal to the number. example  N=3        ( 3, 1, 2, 1, 3, 2 )   I know we can Use Backtracking but is there any other solution.

algorithm					We have words and there positions in a paragraph in sorted order. Write an algorithm to find the least distance for a given 3 words.  eg. for 3 words job: 5, 9 , 17 in: 4, 13, 18 google: 8, 19, 21 ... ... Answer: 17, 18, 19 Can you extend it to "n" words?  Context: In Google search results, the search terms are highlighted in the short paragraph that shows up. We need to  find the shortest sentence that has all the words if we have word positions as mentioned above.

algorithm					Given a M * N matrix, if the element in thematrix is larger than other 8 elements who stay around it, then named thatelement be mountain point. Print all the mountain points.

algorithm					The cows and bulls game, Player A chooses a word and player B guesses a word. You say bulls when a character in the player B's guess match with a character in player A's word and also it is in the corect position as in A's word. You say cows, when a character in the player B's word match the character in player A, but it is not in the correct position. The characters are case insensitive. Given two words player A's and player B's,Write a function that return the number of bulls and no of cows. For example, A - Picture B-  Epic, bulls -0, cows - 4 A - forum B - four, bulls -  3 cows - 1

algorithm					Find Maximum sum subarray such that no elemnt in subarray is repeated https://www.facebook.com/photo.php?fbid=10152820917104183&set=pcb.1523587287892659&type=1&theater

algorithm					Asked at Walmart Labs ---------------------------------- There is a row of seats. Assume that it contains 15 seats adjacent to each other. There is a group of people who are already seating in that row randomly. i.e. some are sitting together & some are scattered.  Take the row as a String in java.  The seat which is occupied is marked with a character 'X' & which is not occupied is marked with a dot '.'   Now your target is to make the whole group sit together i.e. next to each other and without having any vacant seat between them in such a way that the total number of hops or jumps at the end of the grouping them together should be minimum.  Ok let me try to explain you in details.  Here is the row having 15 seats represented by the String (0, 1, 2, 3, ......... , 14) -                 . . . . x . . x x . . . x . .   Now to make them sit together one of approaches is -   . . . . . . x x x x . . . . .    Following are the steps to achieve this -            1 - Move the person sitting at 4th index to 6th index -   Number of jumps by him =   (6 - 4) = 2            2 - Bring the person sitting at 12th index to 9th index - Number of jumps by him = (12 - 9) = 3           ------------------------------------------------------------------------------------------------------------------------------------------------------------           So now the total number of jumps made = ( 2 + 3) = 5 which is the minimum possible jumps to make them seat together.  There are also other ways to make them sit together but the number of jumps will exceed 5 & that will not be minimum.  For example bring them all towards the starting of the row i.e. start placing them from index 0. In that case the total number of jumps will be ( 4 + 6 + 6 + 9 ) = 25 which is very costly and not an optimized way to do this movement.  Now write an algorithm which will return the minimum number of jumps required to make them sit together.

algorithm					write code to validate if the input string has redundant braces?  ((a+b)) - Has redundant braces. (a+(b+c)) - This doesn't has redundant braces.

algorithm					Find the unique number that is present only once in array while all the others are present three times. Example: 2,3,5,1,2,2,5,3,5,3 Answer : 1  as 2,3,5  are repeated three times  Complexity should be better than O(nlogn)

algorithm					Given the relative positions (S, W, N, E, SW, NW, SE, NE) of some pairs of points on a 2D plane, determine whether it is possible. No two points have the same coordinates. e.g., if the input is "p1 SE p2, p2 SE p3, p3 SE p1", output "impossible".

algorithm					Given an array of integer, find the number of un-ordered pairs in that array, say given {1, 3, 2}, the answer is 1 because {3, 2} is un-ordered, and for array {3, 2, 1}, the answer is 3 because {3, 2}, {3, 1}, {2, 1}.  Obviously, this can be solved by brute force with O(n^2) running time, or permute all possible pairs then eliminate those invalid pairs.  My question is does any body have any better solution and how would you do it because it seems like a dynamic programming problem. A snippet of code would be helpful

algorithm					given expression with operands and operators (OR , AND , X-OR) , in how many ways can u evaluate the expression to true, by grouping in different ways? Operands are only true and false.  for example   true & false | true  ^ false can be grouped to true & ((false | true) ^ false) and so on..  the following wiki of the above question http://en.wikipedia.org/wiki/Boolean_satisfiability_problem

algorithm					Suppose we are given a set L of n line segments in the plane, where the endpoints of each segment lie on the unit circle x^2 + y^2 = 1, and all 2n endpoints are distinct. Describe and analyze an algorithm to compute the largest subset of L in which no pair of segments intersects.

data-structures					1. Difference between arrays and link list 1.1 How to prepend each of the above with extra data 2. Hash-table. What datastructure to use to create one. How to resolve collision

data-structures					given preorder traversal  [5,3,2,4,8,7,9] of a BST, how do we identify the leaf nodes without building the tree ?  @Anonymous Thanks for the reply! Please try other use cases like, only single leaf node

data-structures					Given a set of possibly overlapping rectangles in different levels (All of which are "not rotated", can be uniformly represented as (left-bottom,right-top) tuplets), return a minimal set of (non-rotated) non-overlapping rectangles, that occupy the same area.   The rectangle at lower level has more priority than at higher levels.

data-structures					Given an integer target and binary tree (not a binary search tree!) each of whose nodes contains an integer (which may be positive or negative), find the set of all subtrees whose sum equals the given target. The sum of a subtree is just the sum of the integers contained in its nodes. Note that the subtree does not have to contain all child nodes - it can be any set of connected nodes.

data-structures					Print the longest path from root to leaf in a Binary tree (Basically the nodes that lie on the height path).

data-structures					You are given a function getNum() that returns a random number in the range 1 to 10 million with repetitions. However, it may also return -1 when it no longer provides numbers. Write a function that calls getNum() continuously until it returns -1 (if a repetition, should not store it); as soon as u see -1, stop calling getnum() and print all the numbers seen so far in a sorted way. Condition: You have got very limited memory to work with.

data-structures					A program stores total order numbers arrived at different time. For example, at 1.15 pm the program got 15 order, at 1.30 pm, the program got 20 order and so on.Now we need to design the data structure so that we can query the total orders we got in a time range efficiently. For this example, we can query as How many orders we have got between 1 and 2 pm? Ans will be 15+ 20 = 35

data-structures					Given two sorted linked lists of integers write an algorithm to merge the two linked lists such that the resulting linked list is in sorted order. You are expected to define the data structure for linked list as well. Analyze the time and space complexity of the merge algorithm.

data-structures					This is was asked in Amazon SDE online test from Hacker rank.  Initech is a company which has CEO Bill and a hierarchy of employees. Employees can have a list of other employees reporting to them, which can themselves have reports, and so on. An employee with at least one report is called a manager.  Please implement the closestCommonManager method to find the closest manager (i.e. farthest from the CEO) to two employees. You may assume that all employees eventually report up to the CEO.  Tree structure: Bill -> Dom, Samir, Michael Dom -> Bob, Peter, Porter Peter -> Milton, Nina  Sample Data: CEO Bill has 3 employees reporting to him: {Dom, Samir, Michael} Dom has three reports { Peter, Bob, Porter} Samir has no reports {} Michael has no reports {} Peter has 2 reports {Milton, Nina} Bob has no reports {} Porter has no reports {} Milton has no reports {} Nina has no reports {}  Sample calls: closestCommonManager(Milton, Nina) = Peter closestCommonManager(Nina, Porter) = Dom closestCommonManager(Nina, Samir) = Bill closestCommonManager(Peter, Nina) = Peter

data-structures					How to find middle element in a linked list without knowing the length of the linked list

data-structures					Design a data structure which could perform the following operations in O(1): - Insert(), Delete(), Search(), getRandom()  getRandom() should pick a "random" element from your data structure, and should not be predictable (for instance always picking the "first" element from your DS)

data-structures					You are given a stream of incoming strings. Design a data structure, which at any instant, could tell the 100 most repeated words in constant time.

data-structures					Given a 4*n block, find number of different ways of filling it with 1*2 smaller blocks. Rotation of smaller blocks is allowed.

data-structures					Given an array of numbers, for every index i, find nearest index j such that a[j] > a[i].If such an index doesnt exist for i, 1 should be printed.

data-structures					Data structure which supports both map operations and array operations without time complexity penalty.

data-structures					How to find if a given expression is a valid arithmetic expression? Eg:(())()) - Invalid expression, (()()) - Valid expression

data-structures					Given a linkedlist, write an algorithm to divide the linkedlist into two linkedlists, the first contains the Fibonacci numbers in the list and the second contains the non-Fibonacci numbers. Test the algorithm after developing the code

data-structures					Suppose you have a incoming stream of numbers and a method like T* readNextNumber() to read them, and each time there is only limited amont of them coming in and readNextNumber would return null if no more available. implement a method to calculate the median of all numbers you have read.  The key point to the question is figure out the data structure to store those numbers you have read and I stopped at a balance tree, the interviewer told me it should be 2 heaps, one ascending and one descending, plus a median value between them. The final algorithm I figure out based on it is each time compare the new number with median, if bigger than it insert to the descending heap at the right side of the median else to the left, recalculate the median by checking heap sizes, the new median would be either current median, max of the left heap or min of the right heap.

data-structures					Design a data structure which should have following operation. Insert, Delete, Random access

data-structures					Design a data structure in which we can do all CRUD operations in O(1) ?  CRUD- Create, Retrieve, Update, Delete

data-structures					A single-elimination tournament with 64 teams. Before the tournament, fans construct fantasy brackets for their tournament predications. Design a data structure for storing fan brackets and algorithm to score their brackets against a winning bracket. Assume we will then need to quickly score a players predictions (1 point per successful round prediction) and your solution should be optimal enough to handle millions of fan brackets with minimal data.

data-structures					Design a data structure that supports kind of full text search but in numbers.  We are given file with lot of 10-digits numbers, for example:  1234 567 890 4124 123 123 3123 123 322  On a given number X we should return all numbers that contain X.  For example, if the number 123 was given, we should return all numbers (from the list above) because 123 is in all of them.  If the number 41 was given we should return only the middle number - because the number 41 is only in it.

data-structures					Tech Screening Question 1 : You will be given a stream of integers, and a integer k for window size, you will only receive the streams integers one by one. whenever you receive an integer, you have to return the maximum number among last k integers inclusive of current entry.  Interviewer was expecting O(N) solution for N asks.  Edits: Interviewer was expecting O(N) Time + O(1) avg case space complexity solution for N asks. and integers are not given in a array, every time only one integer will be passed as input to your method.

data-structures					How would you increase efficiency of a hive query?

data-structures					Given an array of integers and a number. WAP to find the pairs which sum of upto given number.  I solved it. Then he asked about writing test cases for this function.  I wrote below test cases  1.) All the elements should be number. 2.) Length of array should not be 0. 3.) Array itself should not be null. 4.) Given number, arrayLength can be represented by 32bits or 64 bits. 5.) number should not be negative. 6.) Input does not has pair, It should return false 7.) Input has pair, It should return true 8.) Input has all negative values and pair exists, then function should return true 9.) Input has all negative values and pair does not exists, function should return false  He told that he is looking for more test cases. Can you guys think of some more complex test cases.

data-structures					Write  a function that accepts root of a binary tree and print zigzag level order traversal, each level print in new line. For example, Given tree: 			1 		2		3 	4	      5    6        7 		8              9 output:  1 2 3 7 6 5 4 8 9

data-structures					Write a function that accepts root of a binary tree and return true if it is foldable otherwise return false. A binary tree is foldable if left subtree of root is mirror image if right subtree. For example: Given tree, 			1 		2		3 	4           5    5	       4 		  6            6 output: trus

data-structures					Write  a function that accepts root of a binary tree and print zigzag level order traversal, each level print in new line. For example, Given tree: 			1 		2		3 	4	      5    6        7 		8              9 output:  1 2 3 7 6 5 4 8 9

data-structures					Write a function that accepts two character arrays  each represents a floating point number and return their sum in character array.  For example function accepts "23.45" and "2.5" and return their sum "25.95". Restriction: We cannot use predefined functions / methods or parsing. We have to go with basic operations.

data-structures					You are given two objects, Student and Course, and there exist a many to many relation between them. One student can be enrolled for more than one course and there can be many students enrolled for a single course. Design an effective data structure to store such data keeping in mind that the time complexity for search should be optimum. A search can be for the list of students enrolled for a single course, or for the list of courses a single student is enrolled.

data-structures					Find the depth of Binary search tree without using recursion?

data-structures					Implement a program to reverse the linear linked list in pairs. it should handle both even number of nodes and odd number of nodes. if odd number of nodes, the last node will be the last node after reversion. Do not move the data in the nodes. Do manipulate node pointers/references. the nodes themselves need to be manipulated, not just the data in the nodes. For example, if the initial linear linked is, 1->2->3->4->5 after reverse it should be, 2->1->4->3->5

data-structures					Implement a function that checks if the given binary tree is binary search tree(BST). Use tree operations to solve this. do not try solving by pre-order traversal of the tree and then checking if the array is sorted. instead, traverse the tree for checking if it is BST.

data-structures					Design a data structure to keep track of top k elements out of 2 billion records. Each record is numberd with a key which is 30 bit and a number which is count of how many times the customer has visited us. Come up with an data structure so that the updation of element in 2 billion records will be faster. Getting top k element will be faster

data-structures					How can you determine if an array is pre order representation of a binary tree. I started with the logic of creating binary tree using a pre order array and failure to create the tree will mean that the array is not a pre order representation, but got stuck in middle.

data-structures					New data structure where tree is reversed. Leaves are at the top and root at the bottom. Given two nodes in such DS find the least common ancestor in such tree.

data-structures					Phone Interview with Collabedit.  /** Compute the value of an expression in Reverse Polish Notation. Supported operators are "+", "-", "*" and "/".  * Reverse Polish is a postfix mathematical notation in which each operator immediately follows its operands.  * Each operand may be a number or another expression.  * For example, 3 + 4 in Reverse Polish is 3 4 + and 2 * (4 + 1) would be written as 4 1 + 2 * or 2 4 1 + *  *  * @param ops a sequence of numbers and operators, in Reverse Polish Notation  * @return the result of the computation  * @throws IllegalArgumentException ops don't represent a well-formed RPN expression  * @throws ArithmeticException the computation generates an arithmetic error, such as dividing by zero  *  * <p>Some sample ops and their results:  * ["4", "1", "+", "2.5", "*"] -> ((4 + 1) * 2.5) -> 12.5  * ["5", "80", "40", "/", "+"] -> (5 + (80 / 40)) ->  7  */

data-structures					design and implement a calculater that can calculate expressions like: + 2 4  * 8 ( + 7 12) ( + 7 ( * 8 12 ) ( * 2 (+ 9 4) 7 ) 3 )  (PS:all items are space delimetered.)  Example answers + 2 4 => 2 + 4 = 6 * 8 ( + 7 12) => 8 * ( 7 + 12 ) = 152 ( + 7 ( * 8 12 ) ( * 2 (+ 9 4) 7 ) 3 ) => 7+8*12+2*(9+4)*7+3 = 148

data-structures					there are numbers in between 0-9999999999 (10-digits) which are assigened someone (does not matter which number assigned who)  Write two methods called "getNumber" and "requestNumber" as follows Number getNumber(); boolean requestNumber(Number number);  getNumber method should find out a number that did not assigened than marks it as assiged and  return that number.  requestNumber method checks the number is assigened or not. If it is assigened returns false, else marks it as assiged and return true.  design a data sturucture to keep those numbers and implement those methods

data-structures					You are given a binary search tree and a positive integer K. Return the K-th element of the tree. No pre-processing or modifying of the tree is allowed.

data-structures					You are given a double linked list and an array of pointers to elements in this list (no assumptions can be made on the array - number of pointers, order and duplicates allowed). Return the number of sequences of elements (groups of consecutive elements), pointed by the array.  For example, if this is the array (number relates to index in the list, not the actual pointer value): 9,1,3,7,8,5,2. Then output is 3, representing these sequences: [1,2,3], [5], [7,8,9]

data-structures					Write a function that does an in-order traversal of a tree and prints out the contents (Assume each node has 1 piece of content which is an integer).  Write this function without using recursion (you can assume a library that has stack/queue/list objects with some standard methods is available for use by you).  What is the maximum size your stack can grow to and what is the expected size that your data structure can grow to assuming that the tree has n nodes?

data-structures					Design a TinyURL like Service.

data-structures					How can you design a data structure that can do the following operations in O(1) time:   Insert, Delete, Search, Max which returns the maximum number  I know delete, search and insert can be done O(1) time in a hashmap with a proper hash function. But not sure Max is even possible in O(1) with the presence of delete operation?

data-structures					Constructing Bridges: A River that cuts through a set of cities above and below it. Each city above the river is matched with a city below the river. Construct as many Non-Crossing Bridges as possible. Input: Above Bank >> 7 4 3 6 2 1 5 Below Bank >> 5 3 2 4 6 1 7 are given in pairs: (7,5) (4,3) (3,2) (6,4) (2,6) (1,1) (5,7) Output: (1,1) (3,2) (4,3) (6,4) (7,5)

data-structures					Given a 2^31 x 2^31 tic tac toe board, describe how you would store the state of the game to check if there is a winner.

data-structures					A binary tree represent an organization hierarchy. The root node is the CEO and etc. design a algorithm to print the tree level by level.

data-structures					Implement a vector-like data structure from scratch.  This question was to be done in C or C++.  Discussion topics: 1. Dealing with out of bounds accesses. 2. What happens when you need to increase the vector's size? 3. How many copies does the structure perform to insert n elements? That is, n calls to vector.push_back

data-structures					Given a string (1-d array) , find if there is any sub-sequence that repeats itself. Here, sub-sequence can be a non-contiguous pattern, with the same relative order.  Eg:   1. abab <------yes, ab is repeated 2. abba <---- No, a and b follow different order  3. acbdaghfb <-------- yes there is a followed by b at two places 4. abcdacb <----- yes a followed by b twice  The above should be applicable to ANY TWO (or every two) characters in the string and optimum over time.  In the sense, it should be checked for every pair of characters in the string.

data-structures					Write a program to implement Double Linked List from Stack with min. complexity.

data-structures					The stepping number:  A number is called as a stepping number if the adjacent digits are having a difference of 1. For eg. 8,343,545 are stepping numbers. While 890, 098 are not. The difference between a 9 and 0 should not be considered as 1.  Given start number(s) and an end number(e) your function should list out all the stepping numbers in the range including both the numbers s & e.

data-structures					You're given an array of integers(eg [3,4,7,1,2,9,8]) Find the index of values that satisfy A+B = C + D, where A,B,C & D are integers values in the array.   Eg: Given [3,4,7,1,2,9,8] array The following 3+7 = 1+ 9  satisfies A+B=C+D so print (0,2,3,5)

data-structures					We have 'n' patients and 'm' problems. The problems are of boolean type. Eg diabetes problem would be 'T' if a patient has it or 'F' otherwise. Suggest the data structure you would store this scenario on?  Q: We have a set of problems {diabetes, liver disease, kidney disease} find all the patients who have at least the 3 problems from the set.  The number of patients can be huge (n).  The number of problems not comparatively huge (m).  Which would be the best data structure to store these kind of records, so that we have a better search time.

data-structures					How to impliment Google map Data Structure and algorithm.  1. Zoom in/out 2. horizontal/ vertical.  Assumtion - all the image of earth with pixel\Any other assumption is allowed

data-structures					How google map implemented ? zoom in , zoom out, moving horizontal and moving vertically. Give data Structure and algorithm. Given all the data from satellite which revolve around earth in spiral way.

data-structures					Given a Sorted integer array which is rotated N number of times. You have no idea what that N is. An element in the array can occur more for any number of time. Write a method to search the position of a given element. If there are more than one of the same element, return the position of the first element.

data-structures					JAVA: Given an array say of length 1000; Pick up every value from every 20th index and store it in a separate array. Make sure to loop through all the elements in the array. Example: newArray1 = {0, 20, 40, 60, ..}; newArray2 = {1, 21,41, 61, ..};

data-structures					How will you design, and what data structure will you use for a contact list in a cell Phone. It should  support insert/modify/delete/search functionality like that provided in a cell phone. Suppose some of the entries are  Aman Amazon Neha Aman  and we type 'ama' then the result should show all the above three enteries. Also it should be possible to search using phone numbers.

data-structures					Design a telephone directory for large ppl (he gave example like design for India). fields will be , first name , last name , number . this should be searchable with first name , last name , number as welll. later added more complexity like do the same for organisation where even it contains designations. so this should be searchable with designations.

data-structures					Given a complete binary tree, Find a Max element

data-structures					Write a program to return minimum number of swaps required to convert this binary tree into a BST.

data-structures					Create the data structure for a component that will receive a series of numbers over the time and, when asked, returns the median of all received elements.  (Median: the numerical value separating the higher half of a data sample from the lower half. Example: if the series is  2, 7, 4, 9, 1, 5, 8, 3, 6  then the median is 5.)  Model the data structure for a component that would have these two methods:

data-structures					Implement LRU cache of size 10 which can store Key, Value pair. (get(key) & put(key,value) methods) - If we try to add 11th element, the least recently used element should get removed. - If key already present, overwrite it and mark it as most recently used.

data-structures					For a given binary search tree, replace each node with sum of all node which are greater then of equal to current node.

data-structures					give me the code for : Given a string say "I am a human being" the output should reverse all letters of each word but not the whole string as such. Eg: O/p should be "I ma a namuh gnieb"  I somewhat wrote the code, but i was asked what if there are extra spaces etc. (i am able to write the code sitting at my desktop at one short but there front of interviewer i am struggling. Need to build up my confidence) let me know the best and optimised way of writing this code. Also i suggest people to aviod using inbuilt functions as much as possible    My Answer is as below in perl

data-structures					Given an excel column number convert it to excel column alphabet and reverse.  Example : If column number(starts from 0) = 26 : Column alpha = AA.

data-structures					Print all paths of a binary tree from root to leaf.  Later, extend the solution to work with graphs, careful attention to cycles which you should print as paths as well (without printing visited nodes twice).

data-structures					You are given a large set of integers, which are not sorted. Figure out a method to retrieve the largest 1000 elements, in O(n) run time

data-structures					Find your own method to balance an unbalanced binary tree.(you must not use existing methods like AVL, red black or b trees)

data-structures					Write a function in C to create a new BST which is the mirror image of a given tree.

data-structures					I was asked a question in an interview.   On an office floor , there are e entities - Walls , Cubicles , Coffee Rooms.  In what data structure we should store this design that when a new member joins the company , the cubicle number which is empty and next closest to any coffee room should be assigned to it.  Basically , data structure DS.pop() should return that cubicle number in the most efficient way.  A Person can walk through cubicles to reach a coffee room but not through walls.

data-structures					Write a function to remove all redundant characters in a given string with minimum space and time complexity

data-structures					Given a sorted array of integers, write a function that will return the number with the biggest number of repetitions.  (Asked to refine the solution to be more efficient)

data-structures					Suppose you are supplied with a file containing a list of words like ABC, BCD , CAB ( say each word in new line ). now you have to suggest algorithm for this problem - When a user type some character, we have to suggest him next character and basis of suggestion is that the character you are going to suggest should have maximum occurrence at that position among all these words.  For example , Let's say words are  ABC BCD CBA Now if user types 'A' we have to suggest  him 'B' as next character because if you see at second position in all words 'B' is occurring most number of times ( 2 times ). similarly if he types 'AB' then we need to suggest him third character as 'C' as in third index all words have same occurrence but 'C' comes first.

data-structures					Given two (dictionary) words as Strings, determine if they are isomorphic. Two words are called isomorphic  if the letters in one word can be remapped to get the second word. Remapping a letter means replacing all  occurrences of it with another letter while the ordering of the letters remains unchanged. No two letters   may map to the same letter, but a letter may map to itself.    Example:    given "foo", "app"; returns true     we can map 'f' -> 'a' and 'o' -> 'p'    given "bar", "foo"; returns false    we can't map both 'a' and 'r' to 'o'     given "turtle", "tletur"; returns true   we can map 't' -> 't', 'u' -> 'l', 'r' -> 'e', 'l' -> 'u', 'e' -'r'      given "ab", "ca"; returns true       we can map 'a' -> 'c', 'b'

data-structures					Suppose you have to maintain the stock values of various companies during various periods and return minimum stock value of a particular company over a given period of time.what data structure is best for this.

data-structures					Complete the below function which takes an arraylist and displays the list in the expected output  public class TreePrinter { public static void printTree(Iterable<Relation> rs) { // your code  } }  	public static class Relation { 		String parent; 		String child; 		public Relation(String parent, String child) { ... } } }  Example input: List<Relation> input = newArrayList();  input.add(new Relation(animal, mammal)); input.add(new Relation(animal, bird)); input.add(new Relation(lifeform, animal)); input.add(new Relation(cat, lion)); input.add(new Relation(mammal, cat)); input.add(new Relation(animal, fish));  TreePrinter.printTree(input);  Expected output:  line 1: lifeform line 2:   animal line 3:     mammal line 4:       cat line 5:         lion line 6:     bird line 7:     fish

data-structures					Given an n x n matrix A(i,j) of integers, find maximum value A(c,d) - A(a,b) over all choices of indexes such that both c > a and d > b. Required complexity: O(n^2)

data-structures					Given two trees, find if tree 2 is the mirror image of tree 1.

data-structures					It was a pretty interesting question.  Assume that you are given a fixed set of floating point numbers. Now given a new floating point number 'x', the goal is to efficiently find the number that is closest to 'x' from the fixed set. Question is: what data structure will you actually use for storing the fixed set of floating point numbers to achieve this?  Edit: I missed to add. The interviewer further mentioned that I can not sort and that I can use any amount of time for creating the data structure (meaning this need not be efficient).  Since, I am not allowed to 'sort', I assumed that I can not use BST as I will have to compare numbers while populating the tree. But I didn't clarify it with him; I should have in hindsight.

data-structures					A link list contains following elements

data-structures					You are given a sorted skewed binary tree. How can you create a binary search tree of minimum height from it?

data-structures					A standard chess knight (it moves in its standard way i.e. L shaped OR 2.5 moves) is sitting at the position a1 on an N x N chess board. What is the minimum number of moves it will take to reach the diagonally opposite corner? P.S. - If it were a 8 x 8 chess board, the final destination for the knight would be h8

data-structures					Considering a stream of integers coming in. Design a datastructre to store only n of them. Insert if if does not exist in the datastructre. And if it reaches n, remove the first one inserted into the datastructure.   Datastructure should provide, addition, deletion and search all in O(1) time.

data-structures					I have a list of several million words unsorted.  How can you find the largest and the smallest words that can be typed by a single hand on a qwerty-style keyboard?  Following the rules of finger placement, a word can either be typed fully on the left-hand side of the keyboard, the right-hand side, or both.  Find the largest and smallest left-hand word(s), and the largest and smallest right-hand word(s).   given: millions of words, unsorted given: set of left-hand chars - a,s,d,f,... given: set of right-hand chars - j,k,l...

data-structures					In a Binary Tree, weight of each node is described by the value of the node multiplied by the level (i.e. for root node value is 1* value in root node), And the weight of tree is sum of all the node weights. Find the minimum tree weight out of all the binary trees possible from a given set of numbers.  P.S: No input and no sample data provided

data-structures					I need to store countries, its states and cities in a data structure. The following queries might be used to fetch details  1) find list of states for a country. 2) find list of cities for a state. 3) find the name of the country and state for a city. eg:  1) India -> Gujarat, UP, MP MP -> bhopal,indore Gujarat-> Surat,Ahmedabad, Baroda 2) USA -> Texas, California.. and so on.  Which is the best data structure that can be used to store these details.

data-structures					Implement Object Pool for database connections in the following interface

data-structures					What is the difference between a tree and a map ?

data-structures					How can we implement spell checker.

data-structures					Implement T9 dictionary for mobile phone

data-structures					Two files containing large number, one in each. You have only fopen(), int read(fp), fclose(), fwrite(). Add these two numbers and write in third file with the help of given functions only.

data-structures					Given a server that has requests coming in. Design a data structure such that you can fetch the count of the number requests in the last second, minute and hour.

data-structures					Check if the given binary tree is BST or not.

data-structures					How to find in a binary tree, whether all leaves are at same level or not, and return a boolean value after identifying this.

data-structures					Given a binary tree, a complete path is defined as a path from root to a leaf. The sum of all nodes on that path is defined as the sum of that path. Given a number K, you have to remove (prune the tree) nodes from the tree which lie on a path having sum less than K. Note: A node can be part of multiple paths. So we have to delete it only in case when all paths from it have sum less than K.

data-structures					Given two sorted arrays, find the median of each array. The length of the arrays are m and n and we should not use extra buffer. We should find the median and time complexity should be less than 0(M+N);

data-structures					Print the sum of all nodes of a binary tree, excluding leaf node values.

data-structures					Write a class that will have following functions: long CheckOut() CheckIn(long)  Range of values is 1 to LONG_MAX At any given point in time checkout should return the minimum available LONG number Checkin can return the value back No need to check for border conditions (e.g. check out when all values are exhausted) Implement: 1. long checkout() 2. void checkIn(long input)

data-structures					Q: If you have all the companies that are traded, and live inputs are coming of which company is being traded and what is the volume, how do you maintain the data, so that you can carry out operation of giving the top 10 most traded companies by volume of shares most efficiently. A: I juggled between Hash Map and Max Heap. I said Max Heap, since I can take out top 10 companies in a jiffy with a Max Heap. But then he asked you will need to find a company everytime there is a trade, which will take quite some time in Heap. He pointed out that in real world scenario, number of trades happening, and hence searching of the company and updating it, will be many times more than finding top 10. Which bought me to HashMap. Updations can happen in Real time, while finding top 10 can be done in O(n) or O(nlog(n)) time. Even that wasn't optimal obviously. The interviewer was very nice and friendly type guy. He stressed that at every trade, at most, only 1 company will change in my top 10. This hit me and got me to the correct answer that we keep all actual data in HashMap, but also maintain a MinHeap of 10 most traded company.

data-structures					Q: If I give you a new book, and ask you to create the index which is found at the end of the book, how will you do it. A: I said for constant addition time of words (and page numbers) in the data structure, we can use Hashmap or TRIE. But since output has to be in alphabetic order, we will use a Trie DS, where at the end of each word, we simple store a list of page numbers.

data-structures					You are given the task of creating the address book application for a smart phone. There are some of the top level features you must implement. 1.There will be 1000+ phone book entries and user must get very quick response. 2.On default screen it shows the names of all people in alphabetical ascending order. 3.Using the search option, user can search and it will show only those names starting with those characters which are typed in the search box. You are supposed to compare two different data structures and list down the pros and cons of each and finally recommend the best suited data structure.

data-structures					How will you store a million phone numbers in a space efficient way?

data-structures					Give the algorithm and code to get the depth of the deepest odd level leaf node in a binary tree.

data-structures					There are 2 sorted sets.Find the common elements of those sets e.g. A={1,2,3,4,5,6} B={5,6,7,8,9} o/p C={5,6}  Complexity should ne 0(n+m) where n and m is the size of the first and second set respectively  Which data structure should be used to store the output

data-structures					Design a phonebook dictionary which on input any characters gives names and phone number of all the matching names(prefix)  For instance Rihana 233222232 Ricky   134242444 Peter    224323423 Ron      988232323  If you give R as input it should list  Rihana Ricky and Ron which their contact numbers   If you give ri as input it should list  Rihana, Ricky which their contact numbers

data-structures					Given two arrays of ints that are sets, create a function to merge them to create a new set.  A set must pass on these three conditions: - All values are positive - Sorted - Non-duplicates

data-structures					You have a link list with the following structure: struct Node{ Node*next; Node*other; }  next pointer points to next node, but "other" pointer points to any node in the list, it can be itself or null.  you receive the header of a list with this structure.  you have to copy it(allocate new memory) , you cannot modify the structure, you can not modify the list you are given.

data-structures					Round 3 :  Q 5 : You are given a binary search tree, and a value(data item), you need to tell the left most right cousin in as minimum time and as minimum space ?(need to minimize actual time complexity, he need minimum order of complexity as well as number of node access should be minimum)

data-structures					How can you efficiently implement three stacks in a single array, such that no stack overflows until there is no space left in the entire array space.

data-structures					Print a binary tree in vertical order using singly linked list...complexity should be O(n)

data-structures					Given a seria of points (Xi, Yi), find the line containing the highest number of points from the list.  Per my question he mentioned that I can assume that there is a given function that receives two points and returns the a and b of the line euqation (aX+b)

data-structures					We have n number of sorted array for fixed length. Now we have to merge  these and need to save finaly result array into given array. Note- we can't use extra space except the given array.

data-structures					Given an array containing sequence of bits (0 or 1), you have to sort this array in the ascending order i.e. all 0' in first part of array followed by all 1's.   The constraints is that you can swap only the adjacent elements in the array. Find the minimum number of swaps required to sort the given input array.      Example:   Given the array (0,0,1,0,1,0,1,1) the minimum number of swaps is 3.        Note: You just need  to complete the function given  below for this task. The function is given a binary string as input and returns the required answer.

data-structures					There is a given linked list where each node can consist of any number of characters :- For example  a-->bcd-->ef-->g-->f-->ed-->c-->ba.  Now please write a function where the linked list will return true if it is a palindrome . Like in above example the linked list should return true

data-structures					Implement a thread-safe Blocking queue in C/C++(POSIX) or Java

data-structures					Generate a grey code sequence given the number of digits as input. eg: input=2 output= 00 01 11 10 use minimum space and time complexity

data-structures					Write a C function to print all the elements less than the key element in binary search tree

data-structures					How to stop recursion stack as soon as we find a result. e.g. in a Tree recurion where the Order of the algo is O(n) and suppose we find the result just after 4 calls, can we empty the recursion stack and stop the ececution right away...

data-structures					User inputs a sequence of digits. Every digit is a keystroke, that is equivalent to some character out of a sequence of characters. Digit zero and five mean NULL. The table is given below 0 - NULL              1 - v, t, f, r, q         2 - f, t, k                3 - w, z, b, g             4 - r, s                    5 - NULL  6 - f, i, r 7 - p 8 - l, o 9 - p  Generate all possible character sequence for a given sequence of digits. Ex - If the user input 9801, your program should generate {plv, plt, plf, plr, plq, pov, pot, pof, por, poq} (not necessarily in this order).  This problem is somewhat similar to the SMS problem. It basically boils down to generating a cartesian product of the character sets corresponding to keys.

data-structures					Implement the plusplus operator when we are getting the input as integer array = { 9,9,9,9 }.output will be {1,0,0,0,0}

data-structures					Given an array which contains the parent  of the ith element in the n-ary tree.Parent[i] = -1 for root. Find the height of the tree. Gave O(n2) ,space O(1). Expected Complexity- Linear You can use extra space if you want. Example- {-1 0 1 6 6 0 0 2 7}   0  1 2 3 4 5 6 7 8 0 is the root here. 0 is the parent of 1 5 6  1 is parnt of 2 6 is parent of 3 4  2 is of 7 which is parent of 8.

data-structures					Q1.- Written exam (Amazon, Bangalore)  Given a singly link list and a number 'K', swap the Kth node from the start with the Kth node from the last. Check all the edge cases.  Sample Input: 1->2->3->4->5->6->7->8 and K = 3 Sample Output : 1->2->6->4->5->3->7->8  Sample Input: 1->2->3->4->5->6->7->8 and K = 10 Sample Output: print error "LIST IS OF LESSER SIZE".

data-structures					Q3. Written Exam Amazon(Bangalore)  Given a singly linked list which may or may not contain loop and loop may or may not start from the head node. Count the number of elements in the linked list.

data-structures					Given a dictionary of strings [ strings are in sorted order] you have to find the precedence of characters according to the dictionary.. eat bxy e is ranked above b according to the dictionary.

data-structures					Write Program to find longest common contiguous intersection from 2 lists provided to the function. Example: list1: abcrfghwetf list2: abrfghwwetxyab  Longest common intersection here is: fghw Need Effecient Algorithm to implement this in Java or C, not using arrays.

data-structures					Given a set of intervals, find the interval which has the maximum number of intersections.

data-structures					one unsorted array is given.Find out the index i and j ,j> i for which a[j]  - a[i]  is maximum.perform in linear time complexity

data-structures					Given a set of unique numbers from 1 to 1000, propose a data structure that allows you to perform the following operations in constant time. 1- Insertion, 2- Deletion, 3- Searching, 4- Get any random number.

data-structures					Design a hashtable, you have 1000 items, how many slot would you choose. why.

data-structures					A rooted binary tree with keys in its nodes has the binary search tree  property (BST property) if, for every node, the keys in its left  subtree are smaller than its own key, and the keys in its right  subtree are larger than its own key. It has the heap property if, for  every node, the keys of its children are all smaller than its own key.  You are given a set of n binary tree nodes that each contain an  integer i and an integer j. No two i values are equal and no two j  values are equal. We must assemble the nodes into a single binary tree  where the i values obey the BST property and the j values obey the  heap property. If you pay attention only to the second key in each  node, the tree looks like a heap, and if you pay attention only to the  first key in each node, it looks like a binary search tree.Describe a  recursive algorithm for assembling such a tree

data-structures					How to store a sequence of numbers according to frequency. The most frequent number stores at the beginning

data-structures					Convert a BST to max heap without using extra memory and in as optimum time as possible

data-structures					Propose a data structure that would store numbers, without any knowledge about them, and allow to perform the operations: insert, get median, as efficiently as possible  b. same as before, only this time the numbers are from a group V, which is |V|<<n

data-structures					Given a set of points, find the line that intersects the most number of points

data-structures					I have an array of values which is almost, but not quite sorted, with a few values displaced (say, 50 in 100000). How to sort it most efficiently?

data-structures					What data structure do you prefer to use to implement a stack?

data-structures					Serialize a binary tree to a linked list.

data-structures					Design a deck of cards. What classes? functions? constructors? What functions can you add? Where would you add them. for eg shuffle and deal a card functions. What happens if we need only a particular sort of card eg spades? How would you handle multiple decks? (believe me that was never ending discussion, finally it ended when i started crying :-)

data-structures					When would you use a hash table over a Binary Search Tree?

data-structures					Given a binary tree,find efficiently if its a binary search tree.

data-structures					If in a tree , a node can have more than 2 children , is it possible to traverse it in inorder ? If yes , then how would it be done ?

data-structures					List as many data structures as you can think of.  How do you detect a loop in a linked list?

data-structures					Had my first and second phone interview with Amazon. I was dropped. This site has been a great help towards my preparation and most questions are based on what you find here. Posting my Questions is a small way of saying Thanks!  Interview 1: 1. What is polymorphism. 2. Design an OO parking lot. What classes and functions will it have. It should say, full, empty and also be able to find spot for Valet parking. The lot has 3 different types of parking: regular, handicapped and compact. 3. Coding: I have an integer array where every number appears even number of times and only one appears odd times. Find the number. (I said hashtable and he asked me to write code with Hashtable) 4. What data structure would you use to look up phone numbers for customer names. (I said Hashtable. Asked why hashtable, why not a tree. I said HT has O(1). Asked is order always 1, when more than O(1) in HT.   Second Interview: 1. Starter: Describe your college projects. 2. OO Design: Design a deck of cards. What classes, data structures will you use? How will you shuffle the cards? How will you divide (deck) among players. What class/function do you need to denote players and where will you add them? What class/function do you need to deck? What if I need to add 2 jokers to the deck of 52 cards.  3. Data Structures: How will you use a hashtable to find data in a tree. (Then he rephrased) suppose I have a hashtable, I want to store the data in a tree instead of a bucket. How will I do it. What complexity to find an element.  4. Bits & Bytes: Find if a binary representation of a number is palindrome. The function should work irrespective of number of bytes for an integer. Suppose if our machine is 4 bytes for an int, how will you use the program for 8 byte machine.  5. Unix: Suppose I have 100's of html files in many directories. I want to find the files having phone numbers.   b) Suppose I have 2 files having phone numbers, find the repeating phone numbers. (I said sort and grep). Then he asked what if the lines cannot be sorted.   All the best guys. I think the second interview was challenging since the interviewer was prodding until he heard a leave me alone. So it means that though they are based on questions in cc, be prepared for extensions. I think this site is all you need to prepare for Amazon interview.

data-structures					Given a "directed" graph, write an algo to figure out if the given graph is a tree.

data-structures					1)Implement binary search in a sorted array if array, size and element to be found is given?2)arrange from best to worst:BST, sorted array, unsorted array and hash search based on big O analysis for an average case for inserting, finding an element and finding the range(lowest number and highest number)  3)how would you find the unique lines(that are too long to store in memory) between 2 files tat have a billion lines of data each. How will you find the non-unique lines.

data-structures					Given an array of integers a[ ] and integer x. Return all values from a[ ] where the freq of integer in a[ ] is greater than x.

data-structures					Given a constant number of priorities implement a priority queue with O(1) enqueue and dequeue implementations.

data-structures					Design an algorithm to find whether a given string is formed by the interleaving of two given strings or not.s1= aabccabcs2= dbbabcs3= aabdbbccababccGiven s1,s2,s3 design an efficient algorithm to find whether s3 is formed from the interleaving of s1 and s2.

data-structures					how to divide an integer array into 2 sub-arrays and make their averages equal? e.g. a[left_portion]/left_portion_num == a[right_portion]/right_portion_num.

data-structures					Input an integer array of size n and an integer k (k<=n), output all subsets of size k.

data-structures					For small dataset (less than 200 elements), why is unsorted array has better performance than binary tree? This wasn't the case 20 years ago. (Hint: It has to do with computer architecture.)

coding					Given an array of integers greater than zero, find if it is possible to split it in two (without reordering the elements), such that the sum of the two resulting arrays is the same. Print the resulting arrays.

coding					Cross the street ABC Company is involved in the logistics business.  The company has many outlets and stockyards in a city. The city is like an  N  M NM grid. We consider a single cell of the given grid to be a single block in the city. The stockyard is at the upper-left corner and the outlet is located in the lower right corner. Everyday, one of the employees has to travel from the upper left to the lower right corner for supplies. Each block in the city has a height, where the height of the block located at position (i,j) in the grid is equal to A [ i ] [ j ] A[i][j]. The company wants to change the heights of some of the blocks, so that the employee can enjoy a high-speed drive from the stockyard to the outlet. But this change comes at a certain cost.  Specifically, if they change a block height from x to y, then they must pay exactly  | x  y | |xy| dollars. Please help them find the minimum cost, such that by spending that specific amount, they can get a path from stockyard to the outlet with all blocks along the path having the same height.  In a single move, the employee can move from a block to any of its adjacent blocks. Note that during this journey, the employee is allowed to move in all four directions, fulfilling the condition that he never goes out of the grid at any point in time.  Input :  First line contains two positive integers N and M - number of rows and columns in the city. Then, N lines follow, each containing M integers, where the  j t h jth integer on the  i t h ith line denotes  A [ i ] [ j ] A[i][j].  Output :  The first and only line of output should contain minimum cost.  Constraints :  1<= N, M <=100  1<= height of blocks <=100  Sample Input 5 5 1 1 1 1 1 9 9 9 9 1 1 3 3 3 1 1 9 9 9 9 1 1 1 1 1 Sample Output 6 Explanation Optimal path taken by the employee will be : (1,1) -> (1,2) -> (1,3) -> (1,4) -> (1,5) -> (2,5) -> (3,5) -> (3,4) -> (3,3) -> (3,2) -> (3,1) -> (4,1) -> (5,1) -> (5,2) -> (5,3) -> (5,4) -> (5,5) The height of each block along this path can be changed to  1 1, at a total cost of  6 6. There is no way to get a cost less than this.

coding					Write a program to reveres string from intervals

coding					Find the maximum consecutive 1's in an array of 0's and 1's. Example:  a) 00110001001110 - Output :3 [Max num of consecutive 1's is 3] b) 1000010001  - Output :1 [Max num of consecutive 1's is 1]

coding					Programming Challenge Description:  Develop a service to help a client quickly find a manager who can resolve the conflict between two employees. When there is a conflict between two employees, the closest common manager should help resolve the conflict. The developers plan to test the service by providing an example reporting hierarchy to enable the identification of the closest common manager for two employees. Your goal is to develop an algorithm for IBM to efficiently perform this task. To keep things simple, they just use a single relationship "isManagerOf" between any two employees. For example, consider a reporting structure represented as a set of triples:  Tom isManagerOf Mary Mary isManagerOf Bob Mary isManagerOf Sam Bob isManagerOf John Sam isManagerOf Pete Sam isManagerOf Katie  The manager who should resolve the conflict between Bob and Mary is Tom(Mary's manager). The manager who should resolve the conflict between Pete and Katie is Sam(both employees' manager). The manager who should resolve the conflict between Bob and Pete is Mary(Bob's manager and Pete's manager's manager).   Assumptions: There will be at least one isManagerOf relationship. There can be a maximum of 15 team member to a single manager No cross management would exist i.e., a person can have only one manager There can be a maximum of 100 levels of manager relationships in the corporation  Input:  R1,R2,R3,R4...Rn,Person1,Person2 R1...Rn - A comma separated list of "isManagerOf" relationships. Each relationship being represented by an arrow "Manager->Person". Person1,Person2 - The name of the two employee that have conflict Output:  The name of the manager who can resolve the conflict Note: Please be prepared to provide a video follow-up response to describe your approach to this exercise.  Test 1: Test Input  Frank->Mary,Mary->Sam,Mary->Bob,Sam->Katie,Sam->Pete,Bob->John,Bob,Katie   Expected Output  Mary   Test 2: Test Input  Sam->Pete,Pete->Nancy,Sam->Katie,Mary->Bob,Frank->Mary,Mary->Sam,Bob->John,Sam,John  Expected Output  Mary

coding					Write a method to count the number of 2s between 0 and n.*

coding					Given a packed file with  1Tb of 64-bit doubles (first 8 bytes are first double, next 8 bytes are next, etc) find the exact value of median. For simplicity assume the number of doubles is odd. You can't modify the file and you have only 8Gb of free memory.  Update: you may use no more than two passes through file and your algorithm shouldn't rely on some nature of file - it should work in all cases.

coding					Evaluate the value of an expression given in Reverse Polish notation

coding					This question was asked in the first coding round on-site.  Give two sorted lists List<Integer> a and List<Integer> b.  Find  the Union of these two lists -> the union list should also be sorted the Intersection of these two lists -> Intersection list should also be sorted.

coding					Those who've attended on-site interview with LinkedIn might know that there are 2 rounds of coding interviews. This question was asked in my 2nd round of coding interview,  Given two valid dictionary words of same length, write a function which returns the minimum number of steps to go from the first to the second word. You can change only one character at a time. Also, the word formed at every step should be a valid dictionary word.  Eg: Provide minimum steps to go from 'cat' to 'dog'  cat -> bat -> bet -> bot -> bog -> dog  Ans: 5

coding					Round 6 Question 3 : You are given a word document, you have to print the words with frequencies. Now print the kth rank word in terms of frequency. Print top k words as well by frequencies

coding					Design a cache module for an image server. The server accepts image requests from users and sends them back the images. The cache should always hold in-memory the 10 most recently requested images. The cache should also support multiple requests simultaneously

coding					design a class (give different methods and variables that will be used) that will provide information about the allergy of a patient.  e.g. who reported the allergy(patient/doctor/relative), different symptoms of the allergy that are detected, severity, method that returns when was that  allergy detected in that patient. Along with info about disease if it is not allergy, and can be updated easily, how would you record the time of the disease report using java

coding					write custom pattern match function to match following logic . Matches any single character. * Matches zero or more of the preceding element. The matching should cover the entire input string (not partial). The function prototype should be:

coding					Sparse number is an integer if there are no adjacent 1 in it's binary representation. Like: 5 -> 101 (no adjacent 1)           9 ->  1001  (no adjacent 1) while 6-> 110  is not sparse number. Now you are given an integer find the NEXT BIGGER sparse number.Please mind 'it is next bigger'.

coding					Convert a binary tree into a In Order traversal circular list re-purposing the node's pointers Left & Right as Previous and Next respectively.  Hint: A single node Left & Right points to itself.  Note: This is not a binary search tree.

coding					Given a list of employees and their bosses as a text file   , write a function that will print out a hierarchy tree of the employees.    Sample input =  Sam, Ian, technical lead, 2009 / Ian, NULL, CEO,2007/ Fred, Sam, developer, 2010  The format is name, supervisor, designation, year of joining  The output should be   Ian CEO 2007 -Sam Technical lead 2009 - -Fred Developer 2010

coding					{{ There are 3 machines M1, M2 and M3. Each machine is 90% full of its capacity with integers. Now you have to sort all the integers combined and then store the first 1/3rd in M1, second 1/3rd in M2 and last 1/3rd in M3.   Your objective is to minimize the number of sort operations and number of data transfer operations. Each sort operation/data transfer operation is counted as 1 irrespective of the count of values that are being sorted/transferred.  }}

coding					How to find efficiently the minimum of an array of integers that is the maximum of other arrays?  Example: A = [126, 110, 130] B = [125] C = [105, 115]  The minimum element of array A that is the maximum of B and C is 126

coding					1) You have a folder full of .bin files that are proprietary.   2) You have a class called converter with a "binToTSV" method which you can pass the name of a .bin file and will generate a .tsv file.  3) The TSV file is a tab separated value file with a key on each line, and a value next to it spaced with a tab as such. ------- num_connections	65 latency_ms	70 bandwidth	20 .... //etc. -------  Q: Write a method to calculate the average latency and total bandwidth.

coding					You are given two integer arrays A and B .   1<=i<=len(A) so i is iterator of array A  1<=j<=len(B) so j is iterator of array B    find all the pairs(i,j) such that : i < j and A[i]>B[j]

coding					given a pre and post order kindof a traversal (2 arrays) create an n-ary treee out of it with struct of the form :   struct node {    int data;    struct node *child[MAX];    int child_num; }

coding					given n > 0 fair dice with m > 0 "sides", write an function that returns a histogram of the frequency of the result of dice rolls. For example, for two dice, each with three sides, the results are:  (1, 1) -> 2 (1, 2) -> 3 (1, 3) -> 4 (2, 1) -> 3 (2, 2) -> 4 (2, 3) -> 5 (3, 1) -> 4 (3, 2) -> 5 (3, 3) -> 6  And the function should return:  2: 1 3: 2 4: 3 5: 2 6: 1

coding					Given a string (1-d array) , find if there is any sub-sequence that repeats itself. Here, sub-sequence can be a non-contiguous pattern, with the same relative order.  Eg:   1. abab <------yes, ab is repeated 2. abba <---- No, a and b follow different order  3. acbdaghfb <-------- yes there is a followed by b at two places 4. abcdacb <----- yes a followed by b twice  The above should be applicable to ANY TWO (or every two) characters in the string and optimum over time.  In the sense, it should be checked for every pair of characters in the string.

coding					Implement  bool isBST(Tree * root)

coding					You are given a string S. Each character of S is either a, or b. You wish to reverse exactly one sub-string of S such that the new string is lexicographically smaller than all the other strings that you can get by reversing exactly one sub-string. For example, given abab, you may choose to reverse the substring ab that starts from index 2 (0-based). This gives you the string abba. But, if you choose the reverse the substring ba starting from index 1, you will get aabb. There is no way of getting a smaller string, hence reversing the substring in the range [1, 2] is optimal.  Input: First line contains a number T, the number of test cases. Each test case contains a single string S. The characters of the string will be from the set { a, b }.  Output: For each test case, print two numbers separated by comma; for example x,y (without the quotes and without any additional whitespace). x,y describe the starting index (0-based) and ending index respectively of the substring that must be reversed in order to acheive the smallest lexicographical string. If there are multiple possible answers, print the one with the smallest x. If there are still multiple answers possible, print the one with the smallest y.  Constraints: 1 ? T ? 100 1 ? length of S ? 1000  Sample Input: 5 abab abba bbaa aaaa babaabba  Sample Output: 1,2 1,3 0,3 0,0 0,4

coding					Given a number M (N-digit integer) and K-swap operations(a swap operation can swap 2 digits), devise an algorithm to get the maximum possible integer? Examples: M = 132   K = 1 output = 312 M = 132   K = 2 output = 321 M = 7899  k = 2 output = 9987 M = 8799  and K = 2 output = 9987

coding					Write a recursive  method to get the multiplication of two numbers such that there are minimum number of addition operations.

coding					Given three arrays A,B,C containing unsorted numbers.  Find three numbers a, b, c from each of array A, B, C such that |a-b|, |b-c| and |c-a| are minimum Please provide as efficient code as you can. Can you better than this ???

coding					Write a function which, given two integers (a numerator and a denominator), prints the decimal representation of the rational number "numerator/denominator".    Since all rational numbers end with a repeating section, print the repeating section of digits inside parentheses; the decimal printout will be/must be   Example:  1 , 3 = 0.(3) 2 , 4 = 0.5(0) 22, 7 = 3.(142857)  etc..

coding					Given a number n, write a function that writes a Fibonacci sequence to number n.

coding					Find the longest words in a given list of words that can be constructed from a given list of letters.  Your solution should take as its first argument the name of a plain text file that contains one word per line.  The remaining arguments define the list of legal letters. A letter may not appear in any single word more times than it appears in the list of letters (e.g., the input letters a a b c k can make back and cab but not abba).   Here's an example of how it should work:   prompt> word-maker WORD.LST w g d a s x z c y t e i o b  ['azotised', 'bawdiest', 'dystocia', 'geotaxis', 'iceboats', 'oxidates', 'oxyacids', 'sweatbox', 'tideways']   Tip: Just return the longest words which match, not all.

coding					Write a code to test whether string s2 is obtained by rotating the string s1 by 2 places. e.g S1="amazon" S2="azonam" return true S1="quality" S2="lityqua" return false

coding					Output top N positive integer in string comparison order. For example, let's say N=1000, then you need to output in string comparison order as below: 1, 10, 100, 1000, 101, 102, ... 109, 11, 110, ...

coding					Design a telephone directory for large ppl (he gave example like design for India). fields will be , first name , last name , number . this should be searchable with first name , last name , number as welll. later added more complexity like do the same for organisation where even it contains designations. so this should be searchable with designations.

coding					Given a graph, write a method to check if it is bipartite

coding					Implement thread-safe circular queue that has 2 methods Read & Write n bytes.  The entire design and implementation was open for discussion.  Discussion went for locking, multi threading, boundary cases, all sets of issues related to multi threading..it was quite intense..

coding					Given a linked list: 5 -> 4 -> 3 -> 2 -> 1, produce the following output: 4 -> 2 -> 0 -> 2 -> 1 by substracting the 1st node with nth node, the 2nd with nth -1 node, etc... Only apply the stated action on the first half of the list

coding					Given a array int a[]={2,5,1,9,3,7,2,8,9,3} and the no. of swap operations.We are allowed to do swap operations. swap constraint: exchange only adjacent element. Find the max number that can be formed using swap operations.

coding					public class LogEntry {  public final long startTime; // start time of a job in millisec granularity  public final long endTime; // end time of a job in millisec granularity.  public final long ram; // the amount of ram the job occupies.  public final long jobId;  ... constructor ... }  running total of RAM | | 3GB | ----- | 2GB | ------ | 1GB ----------- |----- ----------- | |____________________________________________________time  Find the peakRAM when the input is a collection of LogEntry objects

coding					give me the code for : Given a string say "I am a human being" the output should reverse all letters of each word but not the whole string as such. Eg: O/p should be "I ma a namuh gnieb"  I somewhat wrote the code, but i was asked what if there are extra spaces etc. (i am able to write the code sitting at my desktop at one short but there front of interviewer i am struggling. Need to build up my confidence) let me know the best and optimised way of writing this code. Also i suggest people to aviod using inbuilt functions as much as possible    My Answer is as below in perl

coding					You are trying to control an on-screen keyboard (e.g. on a television) that looks like this:  a b c d e  f g h i j ...  You can issue the following commands to move the cursor and select letters: u - up d - down l - left r - right ! - select letter  You are given an input string and the length of the rows in the on-screen keyboard. You must produce the sequence of commands needed to type out the input string on the specified keyboard, e.g.: aci, 5 -> !rr!dr!

coding					In Amazon's interview, Round 2 they asked question:  Write a program to print inorder traversal of two trees.   Both values must be printed alternatively.  e.g. if inorder traversal of tree 1 is 10, 15, 20 and tree 2 is 100, 150, 200 then it should print 10, 100, 15, 150, 20, 200.  I tried printing it recursively by calling 2 functions recursively (f1 calls f2, then f2 calls f1 and so on).  I don't know where my approach is going wrong? I know there are other ways to do it as well but in this approach what is the mistake?

coding					In given array find zero and replace the entire row and column with zeros             E.g Input:            1   2   3   4      5   6   7   8      9   10  0   11      12  13  14  15        Output:            1   2   0   4      5   6   0   8      0   0   0   0      12  13  0   15

coding					You need to develop the game Snake. What data structures will you use? Code your solution.

coding					Given a sorted array of integers, write a function that will return the number with the biggest number of repetitions.  (Asked to refine the solution to be more efficient)

coding					Given a board made of 2 x n squares, and boards made of 2 x 1 squares, write a function that will calculate the number of possible ways to arrange the 2 x 1 boards on the 2 x n board, in a way that will fill it completely.   (Asked to refine the solution to be more efficient)

coding					Given N numbers , [N<=10^5] we need to count the total pairs of numbers which have a difference of K. [K>0 and K<10^9]. The solution should have as low of a computational time complexity as possible.  Input Format:  1st line contains N & K (integers). 2nd line contains N numbers of the set. All the N numbers are assured to be distinct.   Output Format:  One integer saying the no of pairs of numbers that have a diff K.  Sample Input #00: 5 2 1 5 3 4 2  Sample Output #00: 3  Explanation: The possible pairs are (5,3), (4,2) and (3,1).

coding					You are given  two string named str1 and str2. Your task is to find  the  minimum window in str1 which contains all characters from string str2.

coding					Find if all the leaf nodes are at same level in binary tree. Recursive and non-recursive approach?

coding					We are given a set of integers with repeated occurences of elements. For Example, S={1,2,2}. We need to print the power set of S ensuring that the repeated elements of the power set are printed only once. For the above S, the power set will be {NULL, {1}, {2}, {2}, {1,2}, {1,2}, {2,2}, {1,2,2}}. So, as per the question requirements, we need to print {NULL, {1}, {2}, {1,2}, {2,2}, {1,2,2}}

coding					Write a function which returns the square root of a given number upto a precision of 0.0001. Only arithematic operations like addition, subtraction, division and multiplication are allowed.

coding					A standard chess knight (it moves in its standard way i.e. L shaped OR 2.5 moves) is sitting at the position a1 on an N x N chess board. What is the minimum number of moves it will take to reach the diagonally opposite corner? P.S. - If it were a 8 x 8 chess board, the final destination for the knight would be h8

coding					given a matrix of size m * n, place k students in such a way so that cheating in an exam could be minimized

coding					Implement enque() function for a fixed size circular queue with synchronization / locking using any atomic opetations.

coding					Write a high performance file search utility program . You are required to write a program that takes command line arguments and searches the required file in the current folder and the sub folders . Search could be for files or folders or both . Below are the four parameters that would be passed . You are also required to so proper exception handling and you code must be optimized as much as possible .  1) A top folder name : Folder from where search would begin. (Ex : C:/MyFolder )   2) Search Option (File /Folder /Both )   3) Search Pattern : A regular expression : (*my*.txt )   4) Timeout in seconds : once the operation treaches this timeout search should be stopped saying " Could not complete operation "  and results obtained till then must be returned .

coding					Given a list of integers, find out the biggest interval that has all its members in the given list. e.g. given list 1, 7, 4, 6, 3, 10, 2 then answer would be [1, 4]. Develop algorithm and write code for this

coding					Two files containing large number, one in each. You have only fopen(), int read(fp), fclose(), fwrite(). Add these two numbers and write in third file with the help of given functions only.

coding					If a=1, b=2, c=3,....z=26. Given a string, find all possible codes that string can generate. Give a count as well as print the strings.  For example: Input: "1123". You need to general all valid alphabet codes from this string.  Output List aabc   //a = 1, a = 1, b = 2, c = 3 kbc     // since k is 11, b = 2, c= 3 alc      // a = 1, l = 12, c = 3 aaw    // a= 1, a =1, w= 23 kw      // k = 11, w = 23

coding					Given a string, find the longest possible even palindrome (length of palindrome is even) from it.  Eg:  Input: abcicbbcdefggfed Output: defggfed (length is 8)  Available palindromes are  1) bcicb - has odd length 2) cbbc - even length 3) defggfed - longest palindrome with even length  This question was asked in a telephonic interview for my friend. I will be posting his solution in a day.

coding					following coins: half dollar, quarters,dime, nickel and penny. Print all the possible combinations of coins that will equal to one dollar.(Ex : (2)  half-dollar , (4) quarter dollar etc )..

coding					Implement a simple regex parser which, given a string and a pattern, returns a boolean indicating whether the input matches the pattern. By simple, we mean that the regex can only contain one special character: * (star). The star means what you'd expect, that there will be zero or more of any character in that place in the pattern. However, multiple consecutive stars are allowed. Some examples of valid input (and expected output):  f(a*b, acb) => true f(abc*, abbc) => false f(**bc, bc) => true

coding					Q: Do you know what is a Binary tree? How would you go about coding for addition of a new element to Binary tree? A: I asked if they want a Binary Tree or a BST? When he said BST I just said we can have a recursive function in which we pass the root of the tree and see if the value to be added is smaller or bigger than the root, and depending on result, we go to left or right of the tree, assuming the left (or right) is not null. If null, just use new to create a memory location, put the value, and use the left reference of the root to link to this new memory.	Simple basic stuff.

coding					I Got this Crazy Question on PHONE INTERVIEW AT GOOGLE:  Design and implement a class to generate random numbers in an arbitrary probability distribution given by an array of integer weights, i.e. for int[] w return a number, n, from 0 to w.length - 1 with probability w[n] / sum(w). Using an existing random number generator with a uniform distribution is permitted.  Example distribution: w = 1, 2, 3, 2, 1  Example probabilities: w / sum = 1/9, 2/9, 1/3, 2/9, 1/9  Example results: n = 0, 1, 2, 3, 4  Documentation:  Class java.util.Random  public int nextInt(int n)  Returns a pseudorandom, uniformly distributed int value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence. The general contract of nextInt is that one int value in the specified range is pseudorandomly generated and returned. All n possible int values are produced with (approximately) equal probability.  Parameters: n - the bound on the random number to be returned. Must be positive. Returns: the next pseudorandom, uniformly distributed int value between 0 (inclusive) and n (exclusive) from this random number generator's sequence Throws: IllegalArgumentException - if n is not positive

coding					If an N X N matrix is given, print it in spiral order. Example: Below is 5 X 5 matrix  i l o v e d i n t e n i e e p a v w r i m a x e c  Print in spiral order. Output is iloveepicexamandinterview

coding					Write a program to print the powerset. E.g. given this set {1,2,3}, it will print {},{1},{2},{3},{1,2},{1,3}, {2,3}, {1,2,3}

coding					Find the k'th largest element in a binary search tree. Write code for

coding					You are given two array lists. One Array List contains information of latitudes and longitudes of all the amazon stores and another array list contains all the possible values of latitudes and longitudes. Find an optimal way to find out all the latitudes and longitudes which are nearest to one pair of amazon store.  ArrayList<latitude, longitude> AmazonStore; ArrayList<latitude, longitude> World;

coding					Write  a function that gets a number n and prints out a random list   of numbers 1..n to the screen. For example:       randlist(5) : 1 5 3 2 4     randlist(6) : 4 6 1 5 3 2   This should be truly random (uniformly spread) and with a O(n) complexity.  Every number should appear only once. Random(n) is given as a tool you can use to generate a single random number between 1-n

coding					Print all valid phone numbers of length n subject to following constraints:  1.If a number contains a 4, it should start with 4 2.No two consecutive digits can be same 3.Three digits (e.g. 7,2,9) will be entirely disallowed, take as input

coding					We define C(n) as the number of ways to take n identical objects out of a bucket, where objects may be taken 1, 2, or 3 at a time.  Example: C(4)=7, because you can take 4 objects in the following 7 ways: 1,1,1,1 2,1,1 1,2,1 1,1,2 2,2 3,1 1,3  Write a function for C(n) in the language of your choice.

coding					Round 1 : Q 2 : longest palindrome in a string ? (Need to tell in O(n) time complexity + O(1) space complexity)

coding					Given an array of integers [2,1,3, 5, 7, 6], re arrange elements such that either even numbers in even locations or odd numbers in odd locations. i.e [2,1,6,5,7,3] in O(n)

coding					given an array of integers generate out put using product of N-1. eg: if input is 1,2,3,4 output will be each product of other int in the array : eg: 2*3*4 , 1*3*4 ,1*2*4 , 1*2*3  solve in N not in N2 algo.

coding					Given preorder traversal array of a BST, recontruct the BST.

coding					User inputs a sequence of digits. Every digit is a keystroke, that is equivalent to some character out of a sequence of characters. Digit zero and five mean NULL. The table is given below 0 - NULL              1 - v, t, f, r, q         2 - f, t, k                3 - w, z, b, g             4 - r, s                    5 - NULL  6 - f, i, r 7 - p 8 - l, o 9 - p  Generate all possible character sequence for a given sequence of digits. Ex - If the user input 9801, your program should generate {plv, plt, plf, plr, plq, pov, pot, pof, por, poq} (not necessarily in this order).  This problem is somewhat similar to the SMS problem. It basically boils down to generating a cartesian product of the character sets corresponding to keys.

coding					Implement the plusplus operator when we are getting the input as integer array = { 9,9,9,9 }.output will be {1,0,0,0,0}

coding					Q1.- Written exam (Amazon, Bangalore)  Given a singly link list and a number 'K', swap the Kth node from the start with the Kth node from the last. Check all the edge cases.  Sample Input: 1->2->3->4->5->6->7->8 and K = 3 Sample Output : 1->2->6->4->5->3->7->8  Sample Input: 1->2->3->4->5->6->7->8 and K = 10 Sample Output: print error "LIST IS OF LESSER SIZE".

coding					Q3. Written Exam Amazon(Bangalore)  Given a singly linked list which may or may not contain loop and loop may or may not start from the head node. Count the number of elements in the linked list.

coding					An infinitely long stream of bits coming  one bit at a time. You have to tell (at any point of time), whether the decimal number is divisible by 3 or not .

coding					Push all the zero's of a given array to the end of the array. In place only. Ex 1,2,0,4,0,0,8 becomes 1,2,4,8,0,0,0

coding					Write a recursive function to convert Binary Code of a number into its equivalent Gray's code and the other way round.

coding					Suppose there is a circle. You have five points on that circle. Each point corresponds to a petrol pump. You are given two sets of data.  1. The amount of petrol that petrol pump will give. 2. Distance from that petrol pump tp the next petrol pump.  (Assume for 1 lit Petrol the truck will go 1 km)  Now calculate the first point from where a truck will be able to complete the circle. (The truck will stop at each petrol pump and it has infinite capacity). Give o(n) solution. You may use o(n) extra space.

coding					"Count and Say problem" Write a code to do following: n                 String to print 0                 1 1                 1 1 2                 2 1 3                 1 2 1 1 ... Base case: n = 0 print "1" for n = 1, look at previous string and write number of times a digit is seen and the digit itself. In this case, digit 1 is seen 1 time in a row... so print "1 1" for n = 2, digit 1 is seen two times in a row, so print "2 1" for n = 3, digit 2 is seen 1 time and then digit 1 is seen 1 so print "1 2 1 1" for n = 4 you will print "1 1 1 2 2 1"  Consider the numbers as integers for simplicity. e.g. if previous string is "10 1" then the next will be "1 10 1 1" and the next one will be "1 1 1 10 2 1"

coding					memset is sometimes used to initialize data in a constructor like the example below. What is the benefit of initializing this way?  Does it work in this example?  Does it work in general ? Is it a good idea in general?  	class A { 	public: 	   A(); 	private: 	   int a; 	   float f; 	   char str[35]; 	   long *lp; 	};  	A::A() 	{ 	   memset(this, 0, sizeof(*this)); 	}

coding					find the longest palindrome in a string?

coding					Write a function to shuffle a deck of 52 cards.  Explain how you would test that the deck was properly shuffled

coding					There is a security keypad at the entrance of a building. It has 9 numbers  1 - 9 in a 3x3 matrix format.  1 2 3 4 5 6 7 8 9  The security has decided to allow one digit error for a person but that digit should be horizontal or vertical. Example: for 5 the user is allowed to enter 2, 4, 6, 8 or for 4 the user is allowed to enter 1, 5, 7.   IF the security code to enter is 1478 and if the user enters 1178 he should be allowed.  Write a function to take security code from the user and print out if he should be allowed or not

coding					Write a program to generate all prime numbers from 2 to N for any N value

coding					A number is called 'desirable' if all the digits are strictly ascending eg: 159 as 1<5<9. You know that your rival has a strictly numeric password that is 'desirable'. Your close ally has given you the number of digits (N) in your rival's password. WAP th\hjtat takes in 'N' as input and prints out all possible 'desirable' numbers that can be formed with N digits.

coding					Write a method to reverse words of string.

coding					Question about Constructors, Destructors, Virtual functions, order in which these are called when creating objects, deleting objects etc.

coding					Design a One shot timer library capable of supporting multiple times simultaneously. Cancel is also supported. Only ONE hardware timer register.So basically, a process/function can call SetTime(10) and it will get notified after 10 seconds. It can also say SetTime(2)... SetTime(7). Then it will get two notifications, one after 2 and one after 7. [SetTime returns a handle]  The process(s) can also issue a cancel. Cancel(handle), to cancel a specific timer they set.   The hardware timer registers, assume decrements by 1 every 1 second. So if you set it to 10, it will notify you after 10 seconds. Basically it interrupts, and lets say calls RegExpired(). You can Read/Write this register anytime very fast (uS).  The key here how you make use of this single register to support any number of timer events that applications/processes are demanding asynchronously.  Discuss the data structure you would use and implement it in C.

coding					Make a nonblocking UART library given a underlying UART hardware, data registers and flags that mark end of transmission and stuff.  This is very common. Simply look for Software UART in embedded systems. Also uses some OS concepts like round-robin, preventing spin locks etc.

coding					Print a Link list in reverse order. Given: PrintReverse(List *head){}  Discuss Pros and cons of Inplace reversal, as compared to reversing by creating a new list. They were looking not only for Memory and Space, but also from a concurrency Point of View.

coding					Write a function to convert integers to roman numerals with 1=I, 5=V, 10=X, 100=C, 1003=M. E.g. 3999 = MMMCMXCIX This was tougher than I thought.

coding					Reverse a linked list iteratively, do it first with single pointers and then do it again with double pointers. Now do it again recursively but not tail-recursive, and then do it again tail-recursively. What do you do if it has a loop?

coding					find max number of repetitions in an array.like {2,3,4,5,2,3,2} max repeat is 2. optimize it for space then in time.

coding					Design a function to find whether a given tree is a mirror of another other tree.

coding					Given an array of positive and negative numbers, find the maximum sum of any subsequence.  Return both the sum and the subsequence.

coding					Write code to reverse a single linked list

coding					Fibonacci Series: write a simple algorithm to find it. He first wanted me to write a recursive one.   What is the running time of this recursive one?  Can you write a better implementation? Its running time? Asked to code it in Java dictate the code.

coding					Write a function: you have an array, which consists of some number which are duplicated 2n times, only one number is duplicated 2n+1 times. Your input parameters are the array and the length of the array. Output the number which is duplicated 2n+1 times. I initially told about XOR, but he then told me XOR is not allowed.

coding					How to delete the kth element from the end of a linked list?

coding					Implement atoi(char *p)

coding					Had my first and second phone interview with Amazon. I was dropped. This site has been a great help towards my preparation and most questions are based on what you find here. Posting my Questions is a small way of saying Thanks!  Interview 1: 1. What is polymorphism. 2. Design an OO parking lot. What classes and functions will it have. It should say, full, empty and also be able to find spot for Valet parking. The lot has 3 different types of parking: regular, handicapped and compact. 3. Coding: I have an integer array where every number appears even number of times and only one appears odd times. Find the number. (I said hashtable and he asked me to write code with Hashtable) 4. What data structure would you use to look up phone numbers for customer names. (I said Hashtable. Asked why hashtable, why not a tree. I said HT has O(1). Asked is order always 1, when more than O(1) in HT.   Second Interview: 1. Starter: Describe your college projects. 2. OO Design: Design a deck of cards. What classes, data structures will you use? How will you shuffle the cards? How will you divide (deck) among players. What class/function do you need to denote players and where will you add them? What class/function do you need to deck? What if I need to add 2 jokers to the deck of 52 cards.  3. Data Structures: How will you use a hashtable to find data in a tree. (Then he rephrased) suppose I have a hashtable, I want to store the data in a tree instead of a bucket. How will I do it. What complexity to find an element.  4. Bits & Bytes: Find if a binary representation of a number is palindrome. The function should work irrespective of number of bytes for an integer. Suppose if our machine is 4 bytes for an int, how will you use the program for 8 byte machine.  5. Unix: Suppose I have 100's of html files in many directories. I want to find the files having phone numbers.   b) Suppose I have 2 files having phone numbers, find the repeating phone numbers. (I said sort and grep). Then he asked what if the lines cannot be sorted.   All the best guys. I think the second interview was challenging since the interviewer was prodding until he heard a leave me alone. So it means that though they are based on questions in cc, be prepared for extensions. I think this site is all you need to prepare for Amazon interview.

coding					I had first round of phone interview today. She asked me to write two very simple codes in C++ and dictate her as I write. She was also writing the code as I was coding. The questions were:  1. Write code to find nth node (from front) in a linked list. 2. Write code to find minimum node in a BST.  Then test cases for both of these questions. Then the same question which need use of "uniq" command of UNIX.

coding					Function which lists all the possible dates for given year.

coding					Background:For any perimeter of a rectangle, there may be multiple different dimensions that result in that specificperimeter. When there are multiple dimensions for the same perimeter, there may also be multiple areas. In other words, any one perimeter can result in different areas depending on the possible combinations of dimensions that can make that perimeter.Definition:A dimension or instance of dimensions for a rectangle is a pair of length and width values. A dimension with length 5 and width 4 is considered the same as a dimension with length 4 and width 5. The area of a rectangle is the length multiplied by the width. The perimeter of a rectangle is equal to the sum of the lengths of all 4 sides or the sum of 2 multiplied by the width and 2 multiplied by the length.Requirement:A finite set of possible perimeters of a rectangle exist given a maximum perimeter, minimum length of any side, and the constraint that all sides are whole numbers; we will call this set U. Find the subset of perimeters in set U where all of the possible dimensions for a perimeter in the subset have areas common with the areas of one or more other perimeters in set U. Your program should take the minimum length of any side and the maximum perimeter, respectively, as command line arguments and output a comma separated list of the perimeters that meet the criteria explained above, sorted from lowest to highest. The program should be submitted in a single Java class with an implemented main function that provides the correct output given the two input arguments.Example:javac YourClass.javajava YourClass 1 6410,14,18,20,22,26,30,34Please make sure your program can be run with the exact syntax above. You can name the class anything you like, but the class name will be passed to a program that will compile it and then run a set of tests on the resulting program. It is important that your class will compile and run from within a local directory, not a package directory.

coding					Write an aligned malloc & free function. Which takes number of bytes and aligned byte (which is always power of  2)Ex. align_malloc (1000,128);it will return memory address multiple of 128 of the size 1000.aligned_free(); it will free memory allocated by align_malloc.

coding					Onsite Interview --Directions1) Write compiling (& working) code on linux2) 2 hours. 3) Total questions 6. Mandatory 4 (but 3 acceptable)Q1) Write a recursive funciton "sum" that computes the sum of all integers between 0 & n. For example, presented the number 10, it would return -15. Next, write a "main" that will drive the function by calling it for each "valid" argument in the program's argument list. If an argument is not an integer then print out an error message, wiht the double quotation marks.For example calling the program with    a.out 23 -12 foo 7should result in output likeSum of all integers between 0 & 23 is 276Sum of all integers between 0 & -12 is -78"foo" is not a numberSum of all integers between 0 & 7 is 28

coding					Write code to verify if an IP address taken as an input string is valid or not.

coding					Get all Rational Numbers such that:1. Both numerator and denominator are strictly 2 digit numbers.2. The last digit of the numerator = first digit of denominator3. If you remove the last digit of numerator and first digit of denominator you will end up with the same numeric valueFor e.g: 16/64

coding					Given an array of integers a[ ] and integer x. Return all values from a[ ] where the freq of integer in a[ ] is greater than x.

coding					I had an interview with Qualcomm about 2 weeks ago (for two days) with two different teams for two different software engineering positions.The interview was very exhausting with questions ranging from sorting and searching algorithms and their efficiency discussions to coding questions in C, puzzles, device driver, boot loader, Networking questions and embedded and RTOS questions to projects I had worked upon during my Masters etc etc.Both teams called me after about two days after the interview and told me that they are interested in making me an offer and I would have to tell them the team I am interested in working with. However the offer details came to me about two weeks after the interviews. The whole process was very professional and I am happy with the way they conducted it.

coding					Design an algorithm to find whether a given string is formed by the interleaving of two given strings or not.s1= aabccabcs2= dbbabcs3= aabdbbccababccGiven s1,s2,s3 design an efficient algorithm to find whether s3 is formed from the interleaving of s1 and s2.

coding					how to divide an integer array into 2 sub-arrays and make their averages equal? e.g. a[left_portion]/left_portion_num == a[right_portion]/right_portion_num.

coding					Input an integer array of size n and an integer k (k<=n), output all subsets of size k.

coding					Write a function that returns the longest palindrome in a given string.  e.g "ccddcc" in the string "abaccddccefe"

coding					Given a value and a binary search tree.Print all the paths(if there exists more than one) which sum up to that value. It can be any path in the tree. It doesn't have to be from the root.

coding					How will you find the longest palindrome in a string? I.e. if the string is XMADAMYX, Your code should print MADAM.

coding					Given a string s1 and a string s2, write  a snippet to say whether s2 is a rotation of s1 using only one call to strstr routine?(eg given s1 = ABCD and s2 = CDAB, return  true)(given s1 = ABCD, and s2 = ACBD , return false)

coding					#5 There are two sentences. Find the common words in the two sentences.

coding					Imagine you have an unbalanced binary search tree.  Design an algorithm which creates a linked list of all the nodes at each depth (eg, if you have a tree with depth D, you'll have D linked lists).  Each node in the linked list should have previous/next pointers (for the linked list) and left/right pointers (from the tree).  Code this algorithm and then test it.

coding					Algorithm: You have a tree (not Binary) and you want to print the values of all the nodes in this tree level by level. Discussed on phone and asked me to email Java code for my algorithm.

coding					Write in java a method to parse an integer from a string

object-oriented-design					Design backend system for bookMyShow.com like system  which supports below use cases:  1) When user selects cities, list of cities is displayed. 2) When user selects city, movie list is displayed. 3) When user selects movie, list of theatre is displayed. 4) When user selects theatre, show timing is displayed. 5) When show timing is selected, user is asked for no of seats that he wants to book 6) When user selects no of seats, seats are displayed to choose from. 7) When user selects seats, then total price is displayed. 8) When total price is selected, then user is directed to payment gateway and payment is done and on payment success, ticket is mailed to him.  More questions on how can we scale the system, and handle concurrent users request for same seat etc.

object-oriented-design					Design OO  food delivery app catering to use cases - 1) User can search different restaurant 2) User can select a restaurant 3) User sees a menu 4) Restaurant can change the menu any time 5) User adds an item from menu  6) User orders the food 7) User can track the order in real time 8) User can cancel the order 9) User pays for the order

object-oriented-design					Design a deck of cards that can be used for different card game applications.  Please code out what you would need for the deck class and a card class.  Implement a deal method.

object-oriented-design					A program stores total order numbers arrived at different time. For example, at 1.15 pm the program got 15 order, at 1.30 pm, the program got 20 order and so on.Now we need to design the data structure so that we can query the total orders we got in a time range efficiently. For this example, we can query as How many orders we have got between 1 and 2 pm? Ans will be 15+ 20 = 35

object-oriented-design					Design and implement the constructor for the minesweeper game that takes in the dimension of the field and number of mines as input

object-oriented-design					Model a restaurant reservation system, where staff can a reservation, pull up, cancel reservations. The reservation system is very simple local to just one terminal at the restaurant not connected to network.

object-oriented-design					Design a Binary search tree using Epic as Input

object-oriented-design					design a class (give different methods and variables that will be used) that will provide information about the allergy of a patient.  e.g. who reported the allergy(patient/doctor/relative), different symptoms of the allergy that are detected, severity, method that returns when was that  allergy detected in that patient. Along with info about disease if it is not allergy, and can be updated easily, how would you record the time of the disease report using java

object-oriented-design					How do you design system for identifying groups of  contacts in phone. Basic info like mail Id, name are different but the person representing them is same. looking for a deduplication way to identify.

object-oriented-design					Given N scientists and K black holes, each scientist can query on radius, size and temperature of a black hole, what data structure would you use? Following queries are important. Which scientist had queried on which black hole. What were the queries made by that scientist.

object-oriented-design					Design a robot that will take your order and make sandwiches for you.  Once I was done with this, I was supposed to extend it to have multiple robots doing this job like an assembly line handling multiple sandwiches and other edible items   Once I handled that, he asked me to create a web service for this that will handle online ordering. He also wanted me to implement fulfillment centers

object-oriented-design					Design a vending machine

object-oriented-design					Design a valet parking system. Requirements of the valet parking system should be: 1. Customer are given a ticket that they can use to redeem to get their vehicle back 2. Parking spots come in three sizes, small, med, large 3. Thee types of vehicles, small, med, large 	-a small vehicle can park in a small, medium, and large spot 	-a medium vehicle can park in a medium and large spot 	-a large vehicle can park in a large spot

object-oriented-design					Design a telephone directory for large ppl (he gave example like design for India). fields will be , first name , last name , number . this should be searchable with first name , last name , number as welll. later added more complexity like do the same for organisation where even it contains designations. so this should be searchable with designations.

object-oriented-design					Design an HTTP downloader that caches results and doesn't block execution (i.e., enables simultaneous downloads).

object-oriented-design					It was a design question. You have to design a game. it has different types of monsters and different weapons. hero would shoot monster. each monster would have some initial health. Each weapon would do some predefined damage to monster. when its health gets 0, monster would die/disappear. and there would be multiple levels. based on level, monster and their behavior would change.

object-oriented-design					What is an interface? How is an interface different than inheritance? Why multiple inheritance not allowed?

object-oriented-design					Design Service like tinyurl

object-oriented-design					Implement T9 dictionary for mobile phone

object-oriented-design					discuss restaurant reservation system design

object-oriented-design					What is the difference between a class method and an instance method?

object-oriented-design					What are immutable objects? What are their Advantages? Design a immutable object with Date object as a member attribute. NOTE : Since Date is mutable, he wanted to check whether I could resolve that. I dint though :(

object-oriented-design					Design a multiple elevators system of skyscraper. Design an algorithm to let person find available elevator soon. How to improve your algorithm?

object-oriented-design					customers want to buy some products but products are out of stock, design a system to notify them when those products are again available?

object-oriented-design					Explain virtual function, up-casting and  applications?

object-oriented-design					Design a data structure that supports integer of unlimited size.Assume that you have unlimited memory. Implement functions to support addition and subtraction.

object-oriented-design					Design Coffee maker .. class diagram

object-oriented-design					Design classes for Themes in UI. A Theme has a font, background colour, background image etc.

object-oriented-design					in singleton class how will delete the obj ?

object-oriented-design					You are creating a calculator for a second grader kids.  Write a function:  int Calculate(char *in)  where char *in is a string that contains an expression like: "1+2" or "-234334-345345" and you return the results accordingly. It is given that there would be two operands and an operator between them.

object-oriented-design					How do you represent the following expression in "class design": (5*3)+(4/2) ? How would an algorithm that computes the value of this expression work?

object-oriented-design					Given two lists l1,l2, show how to merge them in  O(1) time.  The data structures for the lists depends on how you design it.

object-oriented-design					OOP Concept - He wanted me to design a player playing a card game.  My Ans: I explained how a card class can be created with its properties like - Value of a card, Sign of card Then i explained a class for a player.   He asked - how i will represent a player holding a set of cards. My Ans: I told that player is a different class and card is a different type of class as explained. And a card's properties can be inherited to a player's class and can be used to represent "a player holding a set of cards.

object-oriented-design					Design for card game where you have a deck, cards, players. This was straight from Career Cup.  I had given a simpler design first with no factory pattern. He extended the problem to have functionality for creating some different kinds of decks also. So I introduced Factory pattern in my design.

object-oriented-design					Had my first and second phone interview with Amazon. I was dropped. This site has been a great help towards my preparation and most questions are based on what you find here. Posting my Questions is a small way of saying Thanks!  Interview 1: 1. What is polymorphism. 2. Design an OO parking lot. What classes and functions will it have. It should say, full, empty and also be able to find spot for Valet parking. The lot has 3 different types of parking: regular, handicapped and compact. 3. Coding: I have an integer array where every number appears even number of times and only one appears odd times. Find the number. (I said hashtable and he asked me to write code with Hashtable) 4. What data structure would you use to look up phone numbers for customer names. (I said Hashtable. Asked why hashtable, why not a tree. I said HT has O(1). Asked is order always 1, when more than O(1) in HT.   Second Interview: 1. Starter: Describe your college projects. 2. OO Design: Design a deck of cards. What classes, data structures will you use? How will you shuffle the cards? How will you divide (deck) among players. What class/function do you need to denote players and where will you add them? What class/function do you need to deck? What if I need to add 2 jokers to the deck of 52 cards.  3. Data Structures: How will you use a hashtable to find data in a tree. (Then he rephrased) suppose I have a hashtable, I want to store the data in a tree instead of a bucket. How will I do it. What complexity to find an element.  4. Bits & Bytes: Find if a binary representation of a number is palindrome. The function should work irrespective of number of bytes for an integer. Suppose if our machine is 4 bytes for an int, how will you use the program for 8 byte machine.  5. Unix: Suppose I have 100's of html files in many directories. I want to find the files having phone numbers.   b) Suppose I have 2 files having phone numbers, find the repeating phone numbers. (I said sort and grep). Then he asked what if the lines cannot be sorted.   All the best guys. I think the second interview was challenging since the interviewer was prodding until he heard a leave me alone. So it means that though they are based on questions in cc, be prepared for extensions. I think this site is all you need to prepare for Amazon interview.

object-oriented-design					Implement a chess game using object oriented design methods.

object-oriented-design					Given two leaf nodes in a Binary Tree (Not Binary search tree), determine the first common ancestor of these two nodes.

c-plus-plus					n points on a 2D space. You observe the points from (0,0) with viewing direction and viewing angle. Given an array (xn,yn), and a viewing angle v (45 degree), find the direction that can observe max number of points.

c-plus-plus					Program to print string value if each vowel of associated with value 1 and each consonant associated with value 2 print the sum of string value Ex if input:a Print O/p:1 I/p:ab O/p:1+2=3 I/p:abcd O/l:1+2+2+2=7 I/p:abcde O/p1+2+2+2+1=8

c-plus-plus					Get an 0. From user and display its prime factor Example 24 is 2,2,2,3 and 55 is 5,11

c-plus-plus					Assume that const_cast is not in place for C++, can you please write the code to do such casting?

c-plus-plus					Post order traversal for an N-ary tree iterative way. Given, struct Node {    int val;    vector<Node*> children; };  Without modifying original structure.

c-plus-plus					Sort a matrix such that rows in ascending order and columns should be in descending order.

c-plus-plus					Given an array of integers and a number. WAP to find the pairs which sum of upto given number.  I solved it. Then he asked about writing test cases for this function.  I wrote below test cases  1.) All the elements should be number. 2.) Length of array should not be 0. 3.) Array itself should not be null. 4.) Given number, arrayLength can be represented by 32bits or 64 bits. 5.) number should not be negative. 6.) Input does not has pair, It should return false 7.) Input has pair, It should return true 8.) Input has all negative values and pair exists, then function should return true 9.) Input has all negative values and pair does not exists, function should return false  He told that he is looking for more test cases. Can you guys think of some more complex test cases.

c-plus-plus					Point errors (if any) in the following pointer code and explain what it does...  char* cp(char *a) { char *f; f=(char*)malloc(strlen(a)*sizeof(char)); while(*a != 0) {  *f=*a;  f++;  a++; } cout<< f;     return f;  }

c-plus-plus					Given a number,print it in words. 19621 -> One lakh ninety six thousand and twenty one.

c-plus-plus					Abstract We are planning an orienteering game. The aim of this game is to arrive at the goal (G) from the start (S) with the shortest distance. However, the players have to pass all the checkpoints (@) on the map. An orienteering map is to be given in the following format.  ########  #@....G#  ##.##@##  #..@..S#  #@.....#  ######## In this problem, an orienteering map is to be given. Calculate the minimum distance from the start to the goal with passing all the checkpoints. Specification * A map consists of 5 characters as following.  You can assume that the map does not contain any invalid characters and  the map has exactly one start symbol 'S' and exactly one goal symbol 'G'.   * 'S' means the orienteering start.  * 'G' means the orienteering goal.  * '@' means an orienteering checkpoint.  * '.' means an opened-block that players can pass.  * '#' means a closed-block that players cannot pass. * It is allowed to move only by one step vertically or horizontally (up, down, left, or right) to the  next block.  Other types of movements, such as moving diagonally (left up, right up, left down and right down) and skipping one or more blocks, are NOT permitted. * You MUST NOT get out of the map. * Distance is to be defined as the number of movements to the different blocks. * You CAN pass opened-blocks, checkpoints, the start, and the goal more than once if necessary. * You can assume that parameters satisfy following conditions.   * 1 <= width <= 100  * 1 <= height <= 100  * The maximum number of checkpoints is 18.  * Return -1 if given arguments do not satisfy specifications, or players cannot arrive at the goal  from the start by passing all the checkpoints. 1/6 Examination 1 *You can choose Java or C++

c-plus-plus					Given a string (1-d array) , find if there is any sub-sequence that repeats itself. Here, sub-sequence can be a non-contiguous pattern, with the same relative order.  Eg:   1. abab <------yes, ab is repeated 2. abba <---- No, a and b follow different order  3. acbdaghfb <-------- yes there is a followed by b at two places 4. abcdacb <----- yes a followed by b twice  The above should be applicable to ANY TWO (or every two) characters in the string and optimum over time.  In the sense, it should be checked for every pair of characters in the string.

c-plus-plus					Implement  bool isBST(Tree * root)

c-plus-plus					A Multi-threaded server application stops working and the last log message from the application is:

c-plus-plus					Given three arrays A,B,C containing unsorted numbers.  Find three numbers a, b, c from each of array A, B, C such that |a-b|, |b-c| and |c-a| are minimum Please provide as efficient code as you can. Can you better than this ???

c-plus-plus					What do you do if your program does a core dump? (Analyze code dump) Name all the possible ways a program would do core dump.

c-plus-plus					Given a number n, write a function that writes a Fibonacci sequence to number n.

c-plus-plus					Design a telephone directory for large ppl (he gave example like design for India). fields will be , first name , last name , number . this should be searchable with first name , last name , number as welll. later added more complexity like do the same for organisation where even it contains designations. so this should be searchable with designations.

c-plus-plus					Given a string (for example: "a?bc?def?g"), write a program to generate all the possible strings by replacing ? with 0 and 1. Example:  Input : a?b?c?  Output: a0b0c0, a0b0c1, a0b1c0, a0b1c1, a1b0c0, a1b0c1, a1b1c0, a1b1c1.

c-plus-plus					Question 1 / 3 (Odd even level difference) You are given a function calcDifference which takes in the root pointer of a binary tree as it's input. Complete the function to return the sum of values of nodes at odd height - sum of values of node at even height. Consider the root node is at height 1  Sample Input:  Sample Output -74  Explanation: [ (1 + 4 + 5 + 6 + 7 ) ? (2 + 3 + 8 + 9 + 10 + 11 + 12 + 13  + 14 + 15)   = -74 ]

c-plus-plus					A link list contains following elements

c-plus-plus					What happenes when the "new" operator fails to allocate the memory from the heap? I answered it will return NULL. But still he was unhappy...

c-plus-plus					Write a function that given an array of integer and a number k returns true if there is 2 numbers which sum equals to k and false otherwise

c-plus-plus					Given a list of integers, find out the biggest interval that has all its members in the given list. e.g. given list 1, 7, 4, 6, 3, 10, 2 then answer would be [1, 4]. Develop algorithm and write code for this

c-plus-plus					Two files containing large number, one in each. You have only fopen(), int read(fp), fclose(), fwrite(). Add these two numbers and write in third file with the help of given functions only.

c-plus-plus					#include<iostream> #include<exception> int main() { try { cout << "sum"; throw 3; } catch(...) { cout<< "dot"; } catch(int a) { cout << a; } catch(exception e) { cout << "exception"; } return 0; }  what will be the output of the above program?

c-plus-plus					If an N X N matrix is given, print it in spiral order. Example: Below is 5 X 5 matrix  i l o v e d i n t e n i e e p a v w r i m a x e c  Print in spiral order. Output is iloveepicexamandinterview

c-plus-plus					Write a program to sort an array of strings so that all anagrams are next to each other  ex input {god, dog, abc, cab, man} output {abc, cab, dog, god, man}

c-plus-plus					implement your own sizeof() operator..

c-plus-plus					Given a String "abcxrrxabcrr" Find the first repeated string with minimum 3 character?  Answer is "abc" min 3 characters.

c-plus-plus					Q1.- Written exam (Amazon, Bangalore)  Given a singly link list and a number 'K', swap the Kth node from the start with the Kth node from the last. Check all the edge cases.  Sample Input: 1->2->3->4->5->6->7->8 and K = 3 Sample Output : 1->2->6->4->5->3->7->8  Sample Input: 1->2->3->4->5->6->7->8 and K = 10 Sample Output: print error "LIST IS OF LESSER SIZE".

c-plus-plus					Q3. Written Exam Amazon(Bangalore)  Given a singly linked list which may or may not contain loop and loop may or may not start from the head node. Count the number of elements in the linked list.

c-plus-plus					in singleton class how will delete the obj ?

c-plus-plus					If I have 2 pointers A pointing to B and B pointing to A. Is it an error?

c-plus-plus					Explain the difference between calloc and malloc

c-plus-plus					find the longest palindrome in a string?

c-plus-plus					1. What's the difference between a pointer and a reference? 2. What's the difference between a class and a struct? 3. How do you allocate memory in C++? What's the difference between malloc and new?

c-plus-plus					You are creating a calculator for a second grader kids.  Write a function:  int Calculate(char *in)  where char *in is a string that contains an expression like: "1+2" or "-234334-345345" and you return the results accordingly. It is given that there would be two operands and an operator between them.

c-plus-plus					If you were to implement a garbage collector in C++ how will you do it?

c					fun(n){ if (n==0) return k; else if n==1 return 1 else return 2*f(n-1)+4*f(n-2); }  If fun(4) is 88, then what is the value of k.

c					We define an undirected graph g,such that: The total number of nodes in the graph is g_nodes. The nodes are numbered sequentially as 1,2,3.g_nodes. The total number og edges in the graph is g_edges. Each edge connect two distinct nodes(i.e no edge connect a node to itself). The weight of the edge connecting nodes g_to[i] and g_from[i] is g_weight[i]. We define the weight of the path from some start node to some end node to the sum of all edges traversed on the path. Input formate: The first line contain two space-seperated integer describing the respective value of g_node and g_edge. Each line I of the g_edge subsequent lines contain three space seperated integer describing the respective value of g_to[i],g_from[i] and g_weight[i]. The next line contain an integer denoting start The next line contain an integer denoting end. The next line contain an integer denoting w_extra. input 1:  4 4   1 2 2   2 3 1   2 4 2   3 4 3   1      4   5   Output:4 input2:  5 5   1 2 2   1 4 4   2 3 1   3 4 3   4 5 1   1    4   2   output:3  Int mincost(int g_nodes,int g_edged,int* g_from,int* g_to,int* weight,int start,int end,int w_extra) { }

c					how can i merge 2 nodes in a graph in 1 node , need to save the in and out edges and the nodes that was merged for contribution after that   for example a graph implementation in adj list:  1->3->4->6 2->3->4->6 5->4->6  and i want to merge the nodes 3 and 4 , then new nodes should be created 7 as : 1->7->6 2->7->6 5->7->6 7->6  the node 7 also will save [include 3,4 the merged nodes] any one can help with that please   typedef struct AdjListEntry {     int visited;     int index;     struct AdjListNode current; // node iniformation     struct AdjListEntry* next; } AdjListEntry;  typedef struct AdjListNode {     int Uind;     char name[10];     char label[10];     adjOutEddgeLists *outEddges;     //adjInEddgeLists *inEddges; } AdjListNode;  typedef struct adjOutEddgeLists{     AdjListNode *listNode;     adjOutEddgeLists *next; }adjOutEddgeLists;

c					Assume there are 10000 stars in sky, how would you find which star is closest to the earth? in C

c					Write a C program to calculate multiplication between two numbers with repetitive additions

c					Given a linkedlist, write an algorithm to divide the linkedlist into two linkedlists, the first contains the Fibonacci numbers in the list and the second contains the non-Fibonacci numbers. Test the algorithm after developing the code

c					write a program to toggle certain bits in a integer.   Eg.  Inputs : int a, int start bit, int num_of_bits  if a is say 11111010110100000  if start = 6 num_of_bits = 4  output should be (starting 6th bit from right, toggle 4 bits) 11111010001000000

c					Given two numbers a=12, b =36 write a method that return an integer value c=3612, with out using arithmetic and string operations.

c					Given a number,print it in words. 19621 -> One lakh ninety six thousand and twenty one.

c					int fun()  {  	/*write code here.*/  }  int main()  {  	int i=10;  	fun();  	printf("%d",i);  }

c					Given a string (1-d array) , find if there is any sub-sequence that repeats itself. Here, sub-sequence can be a non-contiguous pattern, with the same relative order.  Eg:   1. abab <------yes, ab is repeated 2. abba <---- No, a and b follow different order  3. acbdaghfb <-------- yes there is a followed by b at two places 4. abcdacb <----- yes a followed by b twice  The above should be applicable to ANY TWO (or every two) characters in the string and optimum over time.  In the sense, it should be checked for every pair of characters in the string.

c					A Multi-threaded server application stops working and the last log message from the application is:

c					What do you do if your program does a core dump? (Analyze code dump) Name all the possible ways a program would do core dump.

c					Design a telephone directory for large ppl (he gave example like design for India). fields will be , first name , last name , number . this should be searchable with first name , last name , number as welll. later added more complexity like do the same for organisation where even it contains designations. so this should be searchable with designations.

c					Write a function to return a path from a given node of a Binary tree to the node on its right.   Each node contains a left pointer, a right pointer and a parent pointer  The root node is not provided, the tree is not balanced, the tree is not a Binary search tree  Finding the root node and running BFS from there is not an acceptable solution. You have 30 minutes to give syntactically correct code  I was unable to complete this question and was rejected without further interviews. Perhaps I did something to offend the interviewer, this was for an entry level SDE position

c					Write a function in C to create a new BST which is the mirror image of a given tree.

c					Consider the statement  result = a ? b : c; Implement the above statement without using any conditional statements.

c					Write a piece of code to find out if the system is x86 architecure of Sparc

c					Write a program for finding a minimum element in rotated sorted array(either ascending or descending ) and array contains duplicates.

c					The interviewer asked the following question.

c					The way a Knight  Given a chessboard, consisting of nn cells, several of them are cut. Find the path of minimum length for a Knight from one cell to another. The Knight cant go through cut cells.   Specifications   Input   The first row is set to the number n (2  n  50). Each of the next n lines contains n symbols. The symbol # denotes the cut cell, the point - not cut cell, the symbol @ denotes the initial and final cell of the Knight's path (the chessboard contains two such characters).   Output If the path can not be constructed, print "Impossible". Otherwise display the same map as the input, but check all Knight intermediate positions with symbol @.	  Example Example input  5 ..... .@@.. ..... ..... ..... 5 @..@. ..##. ..... ..... ..... 5 @.... ..#.. .#... ..... ....@   Example output  Sample 1 ...@. .@@.. ....@ ..... ..... Sample 2 @..@. ..##. .@..@ ..@.. @.... Sample 3 Impossible

c					Given two parameters (a target string and a source string), write code that returns the number of times characters found in the source string occur in the target string.  For example, if target="Hello world" and source="llld" then return 4

c					Reverse a string without using any temporary variable. Suppose {{char str[] = "Hello"; then str[] = "olleH";}}}. I told him we can "shift H to o then o to H", similarly so on. But could able to write the code.

c					how much memory can calloc and malloc can allocate???

c					How answer is coming as zero instead of garbage? Does compiler sets "0" to uninitialized variable?

c					c  program to find square root of an interger without using in built functions

c					If an N X N matrix is given, print it in spiral order. Example: Below is 5 X 5 matrix  i l o v e d i n t e n i e e p a v w r i m a x e c  Print in spiral order. Output is iloveepicexamandinterview

c					Given a string we have to find first non-repeating character in the string.... Example:    str="aabbbccccddeffffgg";       Answer is : e

c					For a given integer X, consisting of not more than 6 digits, write the value of the largest palindrome smaller than X and the value of the smallest palindrome larger than X to output.

c					Given a sorted doubly linked list, create a binary tree which is well balanced.   No example was given in the test.  Used the method similar to binary search.

c					Implement the plusplus operator when we are getting the input as integer array = { 9,9,9,9 }.output will be {1,0,0,0,0}

c					int fun(char *a){ printf("%d\n",sizeof(a)); return 1;  } int main() { char a[20]; printf("%d\n",sizeof(fun(a))); } Explain the output.

c					Q1.- Written exam (Amazon, Bangalore)  Given a singly link list and a number 'K', swap the Kth node from the start with the Kth node from the last. Check all the edge cases.  Sample Input: 1->2->3->4->5->6->7->8 and K = 3 Sample Output : 1->2->6->4->5->3->7->8  Sample Input: 1->2->3->4->5->6->7->8 and K = 10 Sample Output: print error "LIST IS OF LESSER SIZE".

c					Q3. Written Exam Amazon(Bangalore)  Given a singly linked list which may or may not contain loop and loop may or may not start from the head node. Count the number of elements in the linked list.

c					Assuming there's no Array data structure in C, how would you implement it.

c					Push all the zero's of a given array to the end of the array. In place only. Ex 1,2,0,4,0,0,8 becomes 1,2,4,8,0,0,0

c					Write Program to find longest common contiguous intersection from 2 lists provided to the function. Example: list1: abcrfghwetf list2: abrfghwwetxyab  Longest common intersection here is: fghw Need Effecient Algorithm to implement this in Java or C, not using arrays.

c					result of this:

c					aligned malloc, asked me exactly y do u allocate extra space for the void *. i tried to explain why, he wasnt listening. in the end he told me what i was trying to tell him

c					implement your own malloc and free for application x, which should control the heap memory usage of the application x.

c					bool foo(int y)  {  int x;  x = y - 1;  return ((x&y) == 0)  }

c					memset is sometimes used to initialize data in a constructor like the example below. What is the benefit of initializing this way?  Does it work in this example?  Does it work in general ? Is it a good idea in general?  	class A { 	public: 	   A(); 	private: 	   int a; 	   float f; 	   char str[35]; 	   long *lp; 	};  	A::A() 	{ 	   memset(this, 0, sizeof(*this)); 	}

c					tell the o/p of: int main(){    int n = 255, i;    char *p = (char *)&n;    for(i = 0; i < sizeof(int); i++)        cout<<*(int *)p<<"\n";    return 0; }

c					50 char *b, q, *r;  200 b = getbuf ();  201 q = *b;  212 R = anotherfunction (b);  213-2003 /* we want to use 'q' and 'r' here */  2000 char * getbuf ()  2001 {  2002 char buff [8];  2003-2050 /* unspecified buff defined here */  2051 return (char*) buff;  2052 }   1. What will be in variable 'q' after line 201 is executed? Under  what conditions might this not be so?     2. Is there an alternative, but equivalent, way to write line  2000? If so, what is it?     3. Is getbuf() a reasonable function?     4. Will getbuf() execute at all?     5. Please comment on line 2051.     6. Is getbuf() good practice, and why?     7. What line not given should be provided for compilation?     8. How, exactly, could one get a second 'char*' to use back from  this function? Be specific in terms of the exact syntax needed. (That  is, provide code.) Another way to state this question is how can this  function be modified to return a 'char*' (that is, it maintains the  same return type) from the function, and an additional 'char *' value  in one function call. Please make sure that your answer will work even  if the size of the char * desired is not known in the outside calling  function. Avoid (do no use) C++ syntax. Include statement in called and  calling functions. Use food programming practice.

c					find the longest palindrome in a string?

c					I was given a simple code which had strUppr() function and asked to find the bugs in the code. Bugs were related to following topics 1. Return value of the function was pointer to an array which is wrong. 2. A while loop with length of a string was written. There length of string was not considered till the end of the array. 3. A range of characters were compared. If (x>a && x<z). Here the bug is that a and z will not be considered.

c					int x; function()=x;  Is it legal or illegal code?Why?

c					Why does destructor in base class need to be declare virtual?

c					Virtual functions and vtable... What happens when a Constructor gives a call to a virtual functions What if it is a pure virtual function

c					Write code and test cases for reversing a C-style string.

c					This question was asked in Microsoft interview. Write a program to determine whether it is a good string or bad string. For ex: {abcdteeh} -  good string (bans{xyzhs}aj) - good string }this{ - bad string {abs{jeu} - bad string  If the string contains the equal no. of corresponding braces, brackets and parathesis. Moreover, if the string is {adbc(xyz}the) bad string... You should take all the possible scenorios and write an efficient code it.

c					Explain how memory allocation works in C++.  Where is the stack vs the heap used?

c					What does appending 'static' to a global variable/function do?

c					difference between struct and class??where to use struct and where to use class??

c					wht is memory leakage in C++??

c					Write the function my2DAlloc. Minimize the number of calls to malloc. Also, the memory should be accessible by the notation arr[i][j].

c					Phone Interview:The guy who interviewed me is a project leader at Bloomberg. He was very arrogant andhis english was very poor.First he asked me to explain what I have worked on at current company. So I explained him the distributed system I built at world's 3rd best research organization. The discussion went on for 30 minutes and at the end He laughed at it and claimed that its not a real distributed system!He then asked following C++ questions:1. Can you have private destructor and private constructor ? explain your answer.2. Can you have virtual constructor ? explain your answer. 3. What design pattern is similar to virtual constructor ?4. Can you have vector of auto_pointer ? explain your answer.5. is this code valid:   auto_pointer<Object> a(new Object());   auto_pointer<Object> b(new Object());   a = b;  My Answer: Yes its valid ( I checked in the book later)  but he insisted that this is invalid code! what an idiot.If he comes on the phone to interview you, just say "No Thanks!"

c					Onsite Interview --Directions1) Write compiling (& working) code on linux2) 2 hours. 3) Total questions 6. Mandatory 4 (but 3 acceptable)Q1) Write a recursive funciton "sum" that computes the sum of all integers between 0 & n. For example, presented the number 10, it would return -15. Next, write a "main" that will drive the function by calling it for each "valid" argument in the program's argument list. If an argument is not an integer then print out an error message, wiht the double quotation marks.For example calling the program with    a.out 23 -12 foo 7should result in output likeSum of all integers between 0 & 23 is 276Sum of all integers between 0 & -12 is -78"foo" is not a numberSum of all integers between 0 & 7 is 28

arrays					You are given an array of integers(with all valid input) You have to write a function which will produce another array, where the value in each index of the array will be the product of all values in the given array accept that index.  Example Array 1: 1 2 3 4 5 Array 2: 120 60 40 30 24. Come up with a solution of O(n^2) can you improve it?

arrays					Return the pivot index of the given array of numbers. The pivot index is the index where the sum of the numbers on the left is equal to the sum of the numbers on the right. Input Array {1,2,3,4,0,6}

arrays					Let's say I have a word "I love chicken", I can break the number of characters in each word, like so: [1] [4] [7] [1,4] [4,7], [1,4,7].  Now let's say I have a max = 5. The phrases with equal or fever than 5 characters are "[I], [love], and [I, love]. The longest phrase is [I,love], which contains 2 words.  Complete the Length function given. It has 2 parameters:  1) An array of integers, named array 2) A maximum number, named max.  int Careercup( int [] array, int max) { }  Example test case 1:  [3,1,2,3]  4  Output expected : 2

arrays					Two friends Kohli and Dhoni want to test their friendship to check how compatible they are. Given a list of n movies numbered 1,2,3....n and asked both of them to rank the movies. Design an algorithm to find compatibility difference between them.  Compatibility difference is the number of mis-matches in the relative rankings of the same movie given by them i.e. if Kohli ranks Movie 3 before Movie 2 and Dhoni ranks Movie 2 before Movie 3 then its a relative ranking mis-match Compatibility difference is the maximum number of mis-matches  Sample Input  5 31245 32415 Sample Output  2 Explanation  Movies are 1,2,3,4,5. Kohli ranks them 3,1,2,4,5, Dhoni ranks them 3,2,4,1,5. Compatibility difference is 2 because Kohli ranks movie 1 before 2,4 but Dhoni ranks it after.

arrays					Find the length of maximum number of consecutive numbers jumbled up in an array.  e.g.: 1, 94, 93, 1000, 2, 92, 1001 should return 3 for 92, 93, 94

arrays					WAP in java to find duplicate element in array in one scan.

arrays					Integer Array Ques: Given an integer array of variable length like so [9, 8, 8, 3] where each item in array could be 0 to 9, write a function that would take would interpret the array [9, 8, 8, 3] as a number 9883 and increment it by 1.  The return of the function would be an integer array containing the addition like so [9,8,8,4].  No zeros in the first position like [0,1,2,3]. I initially suggested a possible solution of process to convert the integer array to String then convert to Integer or Long and then do the addition of 1 and then convert it back to integer array.  That is not allowed when the interviewer change the ques. to not allow that.

arrays					Write program for the following scenario Input Array :- {1,2,3,4,5,5,5,6,7,7} Output:- 5 is repeated 3 times               7 is repeated 2 times

arrays					Round 6 Question 3 : You are given a word document, you have to print the words with frequencies. Now print the kth rank word in terms of frequency. Print top k words as well by frequencies

arrays					Tech Screening Question 1 : You will be given a stream of integers, and a integer k for window size, you will only receive the streams integers one by one. whenever you receive an integer, you have to return the maximum number among last k integers inclusive of current entry.  Interviewer was expecting O(N) solution for N asks.  Edits: Interviewer was expecting O(N) Time + O(1) avg case space complexity solution for N asks. and integers are not given in a array, every time only one integer will be passed as input to your method.

arrays					Rotate a array by N. N can be smaller of greater than the array length.  e.g {0,1,2,4,5,6,7} N =4 should return {5,6,7,4,0,1,2}.  1) I did this using extra array but next I was asked to do without extra array and in o(n) time.

arrays					Given an array of integers and a number. WAP to find the pairs which sum of upto given number.  I solved it. Then he asked about writing test cases for this function.  I wrote below test cases  1.) All the elements should be number. 2.) Length of array should not be 0. 3.) Array itself should not be null. 4.) Given number, arrayLength can be represented by 32bits or 64 bits. 5.) number should not be negative. 6.) Input does not has pair, It should return false 7.) Input has pair, It should return true 8.) Input has all negative values and pair exists, then function should return true 9.) Input has all negative values and pair does not exists, function should return false  He told that he is looking for more test cases. Can you guys think of some more complex test cases.

arrays					You have a function rand5(). This function returns numbers between 1 and 5 randomly with equal probability. Implement a function rand7() which makes use of rand5 to return a number between 1 and 7 randomly with equal probability.

arrays					Consider the 52 cards of a deck. You generated a random sequence for these cards and want to send that sequence to a receiver. You want to minimize the communication between you and the receiver, i.e., minimize the number of bits required to send the sequence.  What is the minimum number of bits required to send the sequence? Hint: It is not 6 x 52

arrays					Find a given element in sorted array.   arr= [1, 2, 3, 4, 5, 6]  follow up: If the sorted array is shifted left by unknown number, modify existing binary search to find a element in modified array  arr = [4, 5, 6, 1, 2, 3]

arrays					Given two sorted arrays, mergesort them into 2nd array that has enough space to accommodate both.

arrays					Write code/ logic to count number of words in a string delimited by " ". Anything apart form " "  are ignore for the counting. String could be very big as big as 5 GB of data. So add logic to handle such large strings..  ex: aaa b c ddd e = Count (5) aaaaaaaaaaa = Count(1) a b c d Count(1) as there are no spaces rather carriage returns are found.  PS: In case above question is not clear do let me know.

arrays					Given a large array of unsigned ints, quickly find two who's sum is 10  Then the interviewer asked me to write test cases.  Followed by how to implement this on a distributed system, where multiple systems can read/write simultaneously on a shared cache (HINT: It is ok if you do not return the first instance)

arrays					Java: You're given a very large array of char's. Write a method to remove duplicates in the array, in place. Optimize for space complexity, not time complexity.

arrays					You're given an array of integers(eg [3,4,7,1,2,9,8]) Find the index of values that satisfy A+B = C + D, where A,B,C & D are integers values in the array.   Eg: Given [3,4,7,1,2,9,8] array The following 3+7 = 1+ 9  satisfies A+B=C+D so print (0,2,3,5)

arrays					Suppose that each row of an n x n array A consists of 1's and D's such that, in any row i of A, all the 1's come before any D's in that row. Suppose further that the number of 1's in row i is at least the number in row i+ 1, for i= 0, 1, ... .n - 2. Assuming A is already in memory, describe a method running in O(n) time (not O(n2) time) for counting the number of 1's in the array A.

arrays					Given three arrays A,B,C containing unsorted numbers.  Find three numbers a, b, c from each of array A, B, C such that |a-b|, |b-c| and |c-a| are minimum Please provide as efficient code as you can. Can you better than this ???

arrays					Design a telephone directory for large ppl (he gave example like design for India). fields will be , first name , last name , number . this should be searchable with first name , last name , number as welll. later added more complexity like do the same for organisation where even it contains designations. so this should be searchable with designations.

arrays					(Bar Raiser Round) Divide the array(+ve and -ve numbers) into two parts such that the average of both the parts is equal.  Input: [1 7 15 29 11 9]  Output: [15 9 1 7 11 29]  Explanation: The average of first two elements is (15+9)/2 = 12, average of remaining elements is (1+7 +11 +29)/4 = 12

arrays					Code a function that receives an array with duplicates and returns a new array keeping the original order of the elements but with the duplicates removed.  For example, if the input were

arrays					You are given a matrix where some pixels are white and some are black. Basically there are different disjoint images in the matrix.  a) Expand/Shrink the images b) Count the no of images c) Color the images d) Rotate the images

arrays					The input is a sequence x1,x2,...,xn of integers in an arbitrary order, and another sequence  a1,a2,..,an of distinct integers from 1 to n (namely a1,a2,...,an is a permutation of  1, 2,..., n). Both sequences are given as arrays. Design an 0(n logn) algorithm to order  the first sequence according to the order imposed by the permutation. In other words, for  each i, Xi should appear in the position given in ai. For example, if x = 17, 5, 1,9, and a =  3, 2, 4, 1, then the outcome should be x = 9, 5, 17, 1. The algorithm should be in-place, so  you cannot use an additional array.

arrays					give me the code for : Given a string say "I am a human being" the output should reverse all letters of each word but not the whole string as such. Eg: O/p should be "I ma a namuh gnieb"  I somewhat wrote the code, but i was asked what if there are extra spaces etc. (i am able to write the code sitting at my desktop at one short but there front of interviewer i am struggling. Need to build up my confidence) let me know the best and optimised way of writing this code. Also i suggest people to aviod using inbuilt functions as much as possible    My Answer is as below in perl

arrays					Move the first n numbers in a 10 element array to the end.  I think the way to do it was to reverse the array and then reverse the first 10-n and then the last n.

arrays					You are given an array with numbers - [11, 3, 11, 11, 3, 2, 0, -2, 2]  You are supposed to write a function that returns the number that appears "odd" number of times.   The solution is obviously using HashMap. But that takes O(n) to create the HashMap and O(n) to lookup. How can one eliminate the second O(n) yet keeping the HashMap?  Hint: Do you really need to count frequency of occurrence of each digit?

arrays					Write a program for finding a minimum element in rotated sorted array(either ascending or descending ) and array contains duplicates.

arrays					Given a 3-D array, if any m[r][c][d] is <=0 mark all the cells in  the entire row,col and depth as zero and return the o/p array

arrays					In given array find zero and replace the entire row and column with zeros             E.g Input:            1   2   3   4      5   6   7   8      9   10  0   11      12  13  14  15        Output:            1   2   0   4      5   6   0   8      0   0   0   0      12  13  0   15

arrays					Given a sorted array of integers, write a function that will return the number with the biggest number of repetitions.  (Asked to refine the solution to be more efficient)

arrays					Given a sorted array with duplicates, move the distinct elements to the top  Ex: 1,1,2,3,4,4,5   -> 1,2,3,4,5

arrays					Arrange the numbers in an array in alternating order. For example if the  array is [a1, a2, a3, a4.. ]arrange the array such that b1<=b2>=b3<=b4 and so on. Sampe Input: 3 5 7 8 4 9 Sample Output: 3 < 5 > 4 < 8 >7 < 9

arrays					Given an integer array. Perform circular right shift by n. Give the best solution.

arrays					Given an array, remove the duplicates and return a unique array keeping the first occurrence of the duplicates and the order.  [@2, @1, @3, @1, @2] --> [@2, @1, @3]

arrays					Given an n x n matrix A(i,j) of integers, find maximum value A(c,d) - A(a,b) over all choices of indexes such that both c > a and d > b. Required complexity: O(n^2)

arrays					Write a function to generate a second array of numbers containing running average of N elements from the original array  So for instance if the original array is, 2,6,4,2,3 and N=3  result = 2,4,3,4,3 you can assume the corner elements can be filled with original elements where there are not enough elements to take avg of N elements

arrays					Given an input array  a={1,2,3,6,2,8----}  product of all numbers=p=a[0]*a[1]*---a[n-1] where n is size of array output arrau should be b={p/a[0],p/a[1],p/a[2]-----}. you should not use division operator.Time complexity should be less than o(n2).

arrays					Given a array of size n. Divide the array in to two arrays of size n/2,n/2. such that average of two arrays is equal.

arrays					Find the majority element which occurs more than n/2 times in an array of n size, which contains duplicate elements in minimum time and space complexity.

arrays					You are given an array of n integers which can contain integers from 1 to n only . Some elements can be repeated multiple times and some other elements can be absent from the array . Write a running code on paper which takes O(1) space apart from the input array and O(n) time to print which elements are not present in the array and the count of every element which is there in the array along with the element number .  NOTE: The array isn't necessarily  sorted.

arrays					In a given array a = {1, 7, 3, 4, 5, 6, 2} Print the indices of all the combinations which lead to a given sum called target. For e.g. if the method is  Void PrintAllSumCombos(int[] arr, int target) - and the array shown above is passed with sum target = 7, then the output should be:  0, 3, 6 0, 5 1 2, 3 4, 6  Note: For simplicity, You may assume the array does not contain any negative numbers and also consider same set of indices with a different order as identical - for e.g. if 2, 3 is already printed, ignore 3, 2 as they are one and the same.

arrays					Given a list of integers, find out the biggest interval that has all its members in the given list. e.g. given list 1, 7, 4, 6, 3, 10, 2 then answer would be [1, 4]. Develop algorithm and write code for this

arrays					Given an array of numbers, arrange it such that all the numbers less than a given key should come before the key and all the numbers greater than the key should come after it. For example: arr = { 0, -1, -2, 2, 0, 3, 5}, given key = 0  answer should be {-1, -2, 0, 0, 2, 3, 5} Order of elements that are smaller or greater than key does not matter i.e. sorting is not expected. So, {-1,-2, 0, 0, 5, 2, 3} is also a correct answer.  Time complexity should not be more than O(n).

arrays					In an array of unsorted integers (you may assume the array may contain +ve, -ve and 0s), write a function  int returnNthMax(int[] arr, int n)  which will return the nth Max number. For e.g. if this is given array {2, -4, 5, 6, 0, 7, -1, 10, 9} and n=1, it should return the max number, 10 and if n=3, it should return 3rd max number, which is: 7.

arrays					Given two array of integers write two functions that will return an Union and Intersection  Time efficient Both time and space efficient implemented

arrays					Consider an array of integers wherein each element is +1 or -1 its preceding element. Given a number, find the first occurence of this number (index) in this array without using linear search.  For example, consider the array : 4 5 6 5 6 7 8 9 10 9 10 (each element in this array is +1 or -1 its preceding element)  Input : 10 (find first occurence of 10 without using linear search) Output : 8

arrays					Eliminate all b and ac in an array of characters, you have to replace them in-place, and you are only allowed to iterate over the char array once.  Examples: abc -> ac ac->'' react->rt

arrays					Sort an array which only has 0's and 1's. Do not use count sort.

arrays					Given a string, find the longest possible even palindrome (length of palindrome is even) from it.  Eg:  Input: abcicbbcdefggfed Output: defggfed (length is 8)  Available palindromes are  1) bcicb - has odd length 2) cbbc - even length 3) defggfed - longest palindrome with even length  This question was asked in a telephonic interview for my friend. I will be posting his solution in a day.

arrays					Given a rotated sorted array, find the MIN of the array.  He pointed out a mistake in my  int middle = (begin+end)/2 which could overflow if the array size was INT_MAX.  Answer was: middle = (end-begin)/2 + begin

arrays					Find the Max sum subsequence in array

arrays					Write a program to find the element in an array that is repeated more than half number of times. Return -1 if no such element is found.

arrays					Length is given as input.Print all possible permutations of numbers between 0-9. Eg: if input length=4 all possible combinations can be 0123, 1234, 5678,9864,...etc all combinations of length from in all numbers between 0-9

arrays					An array contains two sub- sorted arrays. Give an inplace algorithm to sort two sub arrays.  for ex:  I/P:   1 4 5 7 8 9 2 3 6 10 11 O/P:  1 2 3 4 5 6 7 8 9 10 11

arrays					Arrange 1 to N in random order with no duplication.

arrays					Suppose we have r lists with integers from 1 to n. The sum of the lengths of the lists is n. The lists can be different lengths and the same integer may appear in more than one list. Sort all the lists in O(n) time.

arrays					Write a function to sum up two polynomials. Design the data structure for polynomial.

arrays					You are given an unsorted integer array of size N. This array contains integer from range 0 - N (not necessarily distinct and same integer can appear multiple time in an array). You need to find pair of all the elements in array which sum up to N.  First i gave a solution using an extra array of size N to keep count of each integer in original array and was able to give solution in O(n) Time complexity and O(n) space complexity.  Then interviewer asked me to decrease space complexity, for which i gave solution as sorting the given array (in nlogn time) and then find the pairs in O(n) time, and hence total time complexity was O(nlogn) and space complexity as O(1).  But interviewer kept pressing for a better time complexity (than O(nlogn)) with O(1) space complexity.  How is it possible, i could not think of any way.

arrays					Given a 2D array of chars and a raw list of valid words. 1) Find all the valid words from the array. From each element in the array, you can traverse up, down, right or left. Eg,

arrays					Given two arrays of ints that are sets, create a function to merge them to create a new set.  A set must pass on these three conditions: - All values are positive - Sorted - Non-duplicates

arrays					We have n number of sorted array for fixed length. Now we have to merge  these and need to save finaly result array into given array. Note- we can't use extra space except the given array.

arrays					Given an array containing sequence of bits (0 or 1), you have to sort this array in the ascending order i.e. all 0' in first part of array followed by all 1's.   The constraints is that you can swap only the adjacent elements in the array. Find the minimum number of swaps required to sort the given input array.      Example:   Given the array (0,0,1,0,1,0,1,1) the minimum number of swaps is 3.        Note: You just need  to complete the function given  below for this task. The function is given a binary string as input and returns the required answer.

arrays					Given a 2D matrix of characters we have to check whether the given word exist in it or not. eg bool function(char[][],char[])  s f t d a h r y o  we can find "rat in it  (top down , straight ,diagonal).. even in reverse order. with least complexiety.

arrays					Given an array with positive, negative and zeros, arrange the given array such that negatives are on left, zeros in the middle and positives on the right.

arrays					You have 2 sorted Arrays. A and B. A is shorter than B. B has few elements in sorted order and has space for all elements of A. Now Merge these both array so that All elements are sorted. You cant use extra Array. Use Only Array B.

arrays					Implement the plusplus operator when we are getting the input as integer array = { 9,9,9,9 }.output will be {1,0,0,0,0}

arrays					Find the all the sequence from Unsorted array.  Example : {2,4,6,8,10,14,11,12,15,7} is the unsorted array. We have to find out possible sequences.  Output would be :  Seq 1 : {2,4,6,8,10,11,12,15} Seq 2 : {2,4,6,8,10,14,15}   Note : if I pick any element in array than next element would be grater than the previous element.

arrays					Push all the zero's of a given array to the end of the array. In place only. Ex 1,2,0,4,0,0,8 becomes 1,2,4,8,0,0,0

arrays					one unsorted array is given.Find out the index i and j ,j> i for which a[j]  - a[i]  is maximum.perform in linear time complexity

arrays					Given an int array which might contain duplicates, find the largest subset of it which form a sequence.  Eg. {1,6,10,4,7,9,5} then ans is 4,5,6,7  Sorting is an obvious solution. Can this be done in O(n) time

arrays					Given a big unsorted list of 64-bit integers, find an element not in list

arrays					Given an array of ints, is it possible to divide the ints into two groups, so that the sums of the two groups are the same. Every int must be in one group or the other. Write a recursive helper method that takes whatever arguments you like, and make the initial call to your recursive helper from splitArray(). (No loops needed.)   splitArray({2, 2})  true splitArray({2, 3})  false splitArray({5, 2, 3})  true

arrays					An array of size n+1 has integers only from 1 to n. The integers 1 to n can be present 0 or more times in the array. Find the first repeating element in the array. Restrictions: O(n) algo required. Cannot use extra space(not even O(1)).

arrays					If [a1,a2,a3...,an,b1,b2...bn] is given input change this to [a1,b1,a2,b2.....an,bn] , solution should be in-place

arrays					Write an algorithm to find the absolute max subsequence of an array containing both positive and negative numbers in O(n) time   Eg: {100,-2,300} sum=398      {1,2,3,-9} sum=9      {1,2,3,-4} sum=6      {-1,-2}  sum=3

arrays					An array of integers of size n-1, all the elements are form [1,n]. Find the missing number. You can read only one bit in one operation, ie, to read A[i], you need to perform log(A[i]) operations.

arrays					sort an array of 0's and 1's in a most efficient way.

arrays					Find the median of 2 sorted arrays

arrays					find the longest palindrome in a string?

arrays					Given 2 sorted array print their intersection.

arrays					How do you find out intersection between two arrays - when they are sorted / when they are not sorted.  There was discussion on complexity of various algorithms.

arrays					how would you merge two sorted arrays provided not to use a third array nor u can allocate extra space. try to optimize the problem to the best. time complexity should be less than O(n^2)

arrays					Reverse words in a string (e.g. |i||a|m|'\0'| ----> |a|m||i|'\0'|).

java					Given a string, find the longest substring with k distinct characters.  e.g - aaaabbbb, k = 2, aaaabbbb  	asdfrttt k = 3, asd, frttt  [Telephonic Question]

java					input = 8 output = 1 1 1 1 1 1 1 2 3 2 2 2 2 2 2 2 3 3 3 3 3 3 3 4 5 4 4 4 4 4 4 4 5 5 5 5 5 5 5 6 7 6 6 6 6 6 6 6 7 7 7 7 7 7 7 8

java					Remove 3 consecutive duplicates from string. INPUT:aabbbaccddddc OUTPUT:cdc

java					merge two binary search trees

java					Programming Challenge Description:  Develop a service to help a client quickly find a manager who can resolve the conflict between two employees. When there is a conflict between two employees, the closest common manager should help resolve the conflict. The developers plan to test the service by providing an example reporting hierarchy to enable the identification of the closest common manager for two employees. Your goal is to develop an algorithm for IBM to efficiently perform this task. To keep things simple, they just use a single relationship "isManagerOf" between any two employees. For example, consider a reporting structure represented as a set of triples:  Tom isManagerOf Mary Mary isManagerOf Bob Mary isManagerOf Sam Bob isManagerOf John Sam isManagerOf Pete Sam isManagerOf Katie  The manager who should resolve the conflict between Bob and Mary is Tom(Mary's manager). The manager who should resolve the conflict between Pete and Katie is Sam(both employees' manager). The manager who should resolve the conflict between Bob and Pete is Mary(Bob's manager and Pete's manager's manager).   Assumptions: There will be at least one isManagerOf relationship. There can be a maximum of 15 team member to a single manager No cross management would exist i.e., a person can have only one manager There can be a maximum of 100 levels of manager relationships in the corporation  Input:  R1,R2,R3,R4...Rn,Person1,Person2 R1...Rn - A comma separated list of "isManagerOf" relationships. Each relationship being represented by an arrow "Manager->Person". Person1,Person2 - The name of the two employee that have conflict Output:  The name of the manager who can resolve the conflict Note: Please be prepared to provide a video follow-up response to describe your approach to this exercise.  Test 1: Test Input  Frank->Mary,Mary->Sam,Mary->Bob,Sam->Katie,Sam->Pete,Bob->John,Bob,Katie   Expected Output  Mary   Test 2: Test Input  Sam->Pete,Pete->Nancy,Sam->Katie,Mary->Bob,Frank->Mary,Mary->Sam,Bob->John,Sam,John  Expected Output  Mary

java					A program stores total order numbers arrived at different time. For example, at 1.15 pm the program got 15 order, at 1.30 pm, the program got 20 order and so on.Now we need to design the data structure so that we can query the total orders we got in a time range efficiently. For this example, we can query as How many orders we have got between 1 and 2 pm? Ans will be 15+ 20 = 35

java					Given a file (which can be considered as a String with comma delimiter for the complexity of the question) of usernames and a value k, find top k usernames (with number of logins) who logged into the system the most.  For example - Input: User (String) =  user1, user4, user2, user1, user3, user1, user2, user3 k (int) = 2  Output: user1 (3) user2 (2) user3 (2)  - Both user2 and user3 should be included since both has same number of logins  Write a java method to find the output with best time and space complexity.

java					find consecutive integers in a list that give you the biggest sum  Like for -2 5 -1 7 -3 it would be 5 -1 7

java					Test Question, this is a test question

java					Given an array of strings with only lowercase letters   , create a function that returns an array of those same strings, but each string has its letters rearranged such that it becomes a palindrome (if possible, if not, return -1)

java					Implement a function that returns the i-th most popular item sold at xyz company. You cannot rely on any libraries.  Class Item { 	String itemId; 	int quantitySold; }   /** find the i-th most popular item in the list **/ String find(List<Item> items, int i) { // your code goes here }

java					You are given two objects, Student and Course, and there exist a many to many relation between them. One student can be enrolled for more than one course and there can be many students enrolled for a single course. Design an effective data structure to store such data keeping in mind that the time complexity for search should be optimum. A search can be for the list of students enrolled for a single course, or for the list of courses a single student is enrolled.

java					The prime numbers between 1,000,000 and 1,000,100 are: 1000003, 1000033, 1000037,1000039, 1000081, 1000099 and its sum is = 6000292. What is the sum of all prime numbers between 1,000,000,000,000 and 1,000,000,100,000?

java					design a class (give different methods and variables that will be used) that will provide information about the allergy of a patient.  e.g. who reported the allergy(patient/doctor/relative), different symptoms of the allergy that are detected, severity, method that returns when was that  allergy detected in that patient. Along with info about disease if it is not allergy, and can be updated easily, how would you record the time of the disease report using java

java					The problem gives you a sample input data file containing the all the employee-employer relationship information of a company. For example "Peter, John, 2013, software developer--John, NULL, 2012, CEO--David, Peter, 2014, technician..." means there are 3 people int this company (segmented by '--' ), the first 1 is Peter, his boss is John, he entered the company in 2013 as a software developer. The second is John as CEO, with no boss, the third is David as technician, his boss is Peter. The problem is asking to output information in hierarchy style

java					You have a function rand5(). This function returns numbers between 1 and 5 randomly with equal probability. Implement a function rand7() which makes use of rand5 to return a number between 1 and 7 randomly with equal probability.

java					How to find efficiently the minimum of an array of integers that is the maximum of other arrays?  Example: A = [126, 110, 130] B = [125] C = [105, 115]  The minimum element of array A that is the maximum of B and C is 126

java					You have a class that many libraries depend on. You need to modify the class for one application. Which of the following changes require recompiling all libraries before it is safe to build the application?   a. add a constructor  b. add a data member  c. change destructor into virtual  d. add an argument with default value to an existing member function

java					Write a program to implement Double Linked List from Stack with min. complexity.

java					The stepping number:  A number is called as a stepping number if the adjacent digits are having a difference of 1. For eg. 8,343,545 are stepping numbers. While 890, 098 are not. The difference between a 9 and 0 should not be considered as 1.  Given start number(s) and an end number(e) your function should list out all the stepping numbers in the range including both the numbers s & e.

java					How can we divide a large file between multi threads to process it? If we are running a multi threaded application and input is a large file and we have to provide each thread a part of the file to make it fast. How we can achieve it in java?

java					Given a String with print all the possible combinations of the all the characters in the string as a string for Example  "abc" is the input the you should print the below:  abc  ab  ac  a  bc  b  c  There is one invisible string which is actually a blank string.

java					Given a string (for example: "a?bc?def?g"), write a program to generate all the possible strings by replacing ? with 0 and 1. Example:  Input : a?b?c?  Output: a0b0c0, a0b0c1, a0b1c0, a0b1c1, a1b0c0, a1b0c1, a1b1c0, a1b1c1.

java					Input will be a matrix consiting of only 1's n 0's. The 1's represent the lines and 0's its absence.  For eg a matrix 6X7 is shown  0   0   0   1   1   1   1  0   1   1   1   0   1   1  0   1   0   1   0   1   1  0   1   0   1   0   1   1  0   1   1   1   0   1   1  0   0   0   1   1   1   1    In the above matrix, the sequence of 1s represents the lines. These eight lines constitute three  rectangles.   Conditons :   1. The rectangles will always enclose some 0s. e.g. last two vertical lines does not constitute a  rectangle.   2.  A rectangle can contain multiple rectangles    Output : should be no. of rectangles formed in the matrix(intersecting rectangles are also counted).

java					Given a number N, find the smallest even number E such that E > N and digits in N and E are same. Print NONE otherwise. Sample: Input N = 34722641  Output E = 34724126 Input N = 8234961 Output E = 8236194 (instead of 8236149) Java solution

java					Given two words, determine if the first word, or any anagram of it, appears in consecutive characters of the second word. For instance, tea appears as an anagram in the last three letters of slate, but let does not appear as an anagram in actor even though all the letters of let appear in slate. Return the anagram of the first word that has appeared in the second word.  Sample Input 1 tea slate  Sample Output1 ate Sample Input 2 let slate  Sample Output2 NONE  java solution

java					Given a string, complete the given function to recursively remove the adjacent duplicate characters and return the resultant string. If there are no characters left in the resultant string, return "-1" (without quotes). Sample Test Cases Sample Input: ABCCBCBA Output: ACBA  Explanation: (ABCCBCBA --> ABBCBA --> ACBA) Sample Input: AA Sample Output: -1 Java solution

java					Construct an iterator of iterator  Here is the below question format:  // E next(); // Boolean hasNext();  // input: Iterator<Iterator<E>> // output: Iterator<E>  // [[1], [2, 3]] => [1, 2, 3]

java					A professor wants to see if two students have cheated when writing a paper. Design a function : hasCheated(String s1,String s2, int N) that evaluates to true if two strings have a common substring of length N. Additional question after implementation. Assume you don't have the possibility of using String.contains() and String.substring(). How would you implement this?

java					Given a list of 4 billion integers, find an integer not in the list using 4MB of memory. (interview was in Java)

java					How do you write a custom error handler in Java?

java					What is SOAP? What is REST? What are the major differences between SOAP & REST?

java					You need to develop the game Snake. What data structures will you use? Code your solution.

java					Implement data structure for garbage collector in java

java					Given a list of ranges as input ((1,2),(3,4),(3,6),(8,10)),the output would be those ranges that don't overlap.For example, the output could be merging the ranges 1) (1,2),(3,4)  2) (1,2) (3,6) etc  The output cannot contain (3,4),(3,6) as 3 is common to both

java					Using a Java data structure, eliminate all unnecessary/stop words from a string. Assume you are given the string "To be or not to be - that is the question: Whether it is nobler in the mind to suffer, the slings and arrows of outrageous fortune. Or to take up arms against a sea of troubles, and by opposing end them" The unnecessary words to remove are "a", "be", "to", "the", "that", "this", "or" So the resulting string should be like this "not - is question: Whether it is nobler in mind suffer

java					when we have to override equals and hashcode in java..? what will happened if you dont override .. Explain with program.

java					why strings are immutable ?  how many objects will be created in  String temp = "A" + "B" + "C" ; explain your answer in detail.

java					Can you predict the output of the following code?

java					Find the latest version of released software. For e.g1. 2 and 2.2.. latest is 2.2.  eg2: 3.1 and 3.1.3... latest version is 3.1.3... version is passed as string in above format.

java					How will you calculate the size of the object in java ? I gave answer for the serialized objects. The interviewer then modified the question that an ArrayList contains 10 non-serialized objects. How will you find out which object is the heaviest one ? He again added that the ArrayList is not a generic one, it may contain any kind of object like Organisation, Employee, Salary, PersonalDetails,OfficialDetails etc all object type. Now you have to find out which one is the heavy object through java program. He said there is some way you can measure the size of the object. Please help me.

java					Check if the given binary tree is BST or not.

java					This question was asked in todays interview's written test. According to me it should go into infinite waiting, but when I run this code on my computer, it safely ends up printing the value. I executed n number of times but still it finishes without without going into infinite waiting.  Can someone explain.

java					Implement circular queue in Java such that: 1. It should work in multithreaaded environment. 2. If one thread performing EnQueue operation and if queue are full then it should wait untill other not emptied the queue. 3. If some thread tring to do Dequeue operation and if queue is empty, then that thread should wait untill other thread can fill atleast one element in queue.

java					Q: The New operator...how does it work, what are the steps? A: I just said it creates a new memory in the heap and the reference points to it. He seemed satisfied.

java					If an N X N matrix is given, print it in spiral order. Example: Below is 5 X 5 matrix  i l o v e d i n t e n i e e p a v w r i m a x e c  Print in spiral order. Output is iloveepicexamandinterview

java					Coding:

java					What is difference between "volatile" and "static volatile"? Give an example

java					Write a program to sort an array of strings so that all anagrams are next to each other  ex input {god, dog, abc, cab, man} output {abc, cab, dog, god, man}

java					find the substring count from a string without string functions in java? Given String str = "abcdefghcde"; String find = "cde"; Count occurrences of cde in String str

java					What are immutable objects? What are their Advantages? Design a immutable object with Date object as a member attribute. NOTE : Since Date is mutable, he wanted to check whether I could resolve that. I dint though :(

java					How to make object immutable?

java					write a program to perform divison operation of two numbers without using  /,  %,  and  modules operatot

java					How to stop recursion stack as soon as we find a result. e.g. in a Tree recurion where the Order of the algo is O(n) and suppose we find the result just after 4 calls, can we empty the recursion stack and stop the ececution right away...

java					Q1.- Written exam (Amazon, Bangalore)  Given a singly link list and a number 'K', swap the Kth node from the start with the Kth node from the last. Check all the edge cases.  Sample Input: 1->2->3->4->5->6->7->8 and K = 3 Sample Output : 1->2->6->4->5->3->7->8  Sample Input: 1->2->3->4->5->6->7->8 and K = 10 Sample Output: print error "LIST IS OF LESSER SIZE".

java					Q3. Written Exam Amazon(Bangalore)  Given a singly linked list which may or may not contain loop and loop may or may not start from the head node. Count the number of elements in the linked list.

java					You have been asked to deploy a number of robotic domestic helpers (RDH) into a large room to remotely clean it as they move around it. This room is currently rectangular in shape and must be navigated by the RDHs in order to successfully clean the room.  A RDH position and location is represented by a combination of x and y co-ordinates and a letter representing one of the four cardinal compass points. The room is divided up into a grid to simplify navigation. An example position might be 0, 0, N, which means the RDH is in the bottom left corner and facing North.  In order to control a RDH the operator sends a simple string of letters. The possible letters are 'L', 'R' and 'M'. 'L' and 'R' makes the robot spin 90 degrees left or right respectively, without moving from its current spot.  'M' means move forward one grid point, and maintain the same heading.  Assume that the square directly North from (x, y) is (x, y+1).  INPUT: The first line of input is the upper-right coordinates of the arena, the lower-left coordinates are assumed to be 0,0.  The rest of the input is information pertaining to the RDHs that have been deployed. Each RDH has two lines of input. The first line gives the RDHs initial deployed position, and the second line is a series of instructions telling the RDH how to navigate around the room.  The position is made up of two integers and a letter separated by spaces, corresponding to the x and y co-ordinates and the RDHs orientation.  Each RDH will be finished sequentially, which means that the second RDH won't start to move until the first one has finished moving.   OUTPUT The output for each RDH should be its final co-ordinates and heading.  INPUT AND OUTPUT  Test Input: 7 6 2 4 E MMRMMRMRRM 3 4 N LMLMLMLMM  Expected Output: 4 2 E 43e3 5 N

java					Question about java Generics. What it is? Functions and Generics questions.  Best if you study it well.

java					Had my first and second phone interview with Amazon. I was dropped. This site has been a great help towards my preparation and most questions are based on what you find here. Posting my Questions is a small way of saying Thanks!  Interview 1: 1. What is polymorphism. 2. Design an OO parking lot. What classes and functions will it have. It should say, full, empty and also be able to find spot for Valet parking. The lot has 3 different types of parking: regular, handicapped and compact. 3. Coding: I have an integer array where every number appears even number of times and only one appears odd times. Find the number. (I said hashtable and he asked me to write code with Hashtable) 4. What data structure would you use to look up phone numbers for customer names. (I said Hashtable. Asked why hashtable, why not a tree. I said HT has O(1). Asked is order always 1, when more than O(1) in HT.   Second Interview: 1. Starter: Describe your college projects. 2. OO Design: Design a deck of cards. What classes, data structures will you use? How will you shuffle the cards? How will you divide (deck) among players. What class/function do you need to denote players and where will you add them? What class/function do you need to deck? What if I need to add 2 jokers to the deck of 52 cards.  3. Data Structures: How will you use a hashtable to find data in a tree. (Then he rephrased) suppose I have a hashtable, I want to store the data in a tree instead of a bucket. How will I do it. What complexity to find an element.  4. Bits & Bytes: Find if a binary representation of a number is palindrome. The function should work irrespective of number of bytes for an integer. Suppose if our machine is 4 bytes for an int, how will you use the program for 8 byte machine.  5. Unix: Suppose I have 100's of html files in many directories. I want to find the files having phone numbers.   b) Suppose I have 2 files having phone numbers, find the repeating phone numbers. (I said sort and grep). Then he asked what if the lines cannot be sorted.   All the best guys. I think the second interview was challenging since the interviewer was prodding until he heard a leave me alone. So it means that though they are based on questions in cc, be prepared for extensions. I think this site is all you need to prepare for Amazon interview.

brain-teasers					You are given a flat room 1x1 metres, a position of victim in it (v_x, v_y) and a position of a killer (k_x, k_y) both inside this room (in range [0, 1]). Then the killer shoots once at some direction. The bullet reflects of the walls as if it was a light ray - if it falls under angle X degrees, it will reflect at angle X  degrees, if it gets into the corner it just reflects back. If the bullet hits guardian (see below) it stops and killer fails. Write a function that will be given coordinates of victim and a killer and will return a list of coordinates of guardians such that it's impossible for a killer to kill victim.  That is, whichever direction the killer will shoot, the bullet will never reach victim, or will be stopped by a guardian.  Here is an example for the case when we assume the walls don't reflect bullet (for simplicity): killer: (0, 0), victim: (1, 1). The solution to this simplified problem is to place 1 guardian between killer and victim e.g. on (0.1, 0.1).  Your task is to do this with accounting bullet reflection. E.g. in the previous case the killer can shoot at (1/3, 1), the bullet will reflect to (2/3, 0) and finally get to the victim at (1, 1).

brain-teasers					John observers the following while driving to work.       4 were driving a red car.      3 were driving a blue car.     3 were driving a black car.  He also notices that       3 of them were listining to Hip Hop     4 of them were listining to pop music.     3 of them were listining to Rock.  Additionally he notices that,       3 of them reached office before time on Friday.     3 of them reached office before time on Tuesday.     2 of them reached office before time on Wednesday.     2 of them reached office before time on Thursday.  Which of the following practice maximises his chance of getting to office before time.    a) He should drive a red car to work listining to pop music on a friday?   b) He should drive a blue car to work listining to rock music on a Tuesday.  State how did you calculate the probabiltiy for both in your answer.

brain-teasers					an bacteria grows at the speed that it will double its volume per minute. If you put it in a jar, it will fill the jar in one hour. how long will it take to fill a half of the jar?

brain-teasers					Given a string (1-d array) , find if there is any sub-sequence that repeats itself. Here, sub-sequence can be a non-contiguous pattern, with the same relative order.  Eg:   1. abab <------yes, ab is repeated 2. abba <---- No, a and b follow different order  3. acbdaghfb <-------- yes there is a followed by b at two places 4. abcdacb <----- yes a followed by b twice  The above should be applicable to ANY TWO (or every two) characters in the string and optimum over time.  In the sense, it should be checked for every pair of characters in the string.

brain-teasers					The Question is to find 4 numbers between 1 and 40, so that you can get all the numbers between 1 to 40 by doing either of operation below. 1) Either any of the four number itself. 2) creating an expression by combining among the four number, with either addition or subtraction.   For example suppose we have to find four numbers so that we can get numbers between 1-30. The answer to above question is 1,3,6,20.

brain-teasers					You stand in one corner of a large room, and your assistant is in its opposite corner. In front of the assistant is a 4-corner table, with a coin in each of the 4 corners. Your objective is to get the coins to be all heads or all tails. When that happens, the coins start jumping up and down; so, you'll know for sure when it happens. What you can do is to tell your assistant: (a) flip one coin; (b) flip two coins on a side of the table; (c) flip two coins on a diagonal of the table. You can't tell the assistant which coin, which side, or which diagonal to use. You can either think of your assistant as being extremely dumb, or that the table is being constantly rotated by external forces. What is the sequence of commands that you should give to your assistant to make sure the coins start jumping up and down?

brain-teasers					Distributing Medals It's the medal distribution ceremony. 10^6 police officers, numbered from 1 to 10^6, are standing in a line. There are N (1<=N<=1000) iterations of medal distribution. In iteration i (0 < = i < N), count[i] ( 1 < = count[i] < = 100) medals are given to all officers from from[i] to to[i] ( 1 < = from[i] < = to[i] < = 10^6 )  If we sum up the number of medals received starting from the first officer, who would be the first officer for which the cumulative sum exceeds a given medal count THRESHOLD ( 1 < = THRESHOLD < = 10^9 )?  Input/Output Specifications Input format:  You are given 5 inputs:  input1 = N, the number of iterations  input2 = count, the array of medal counts in each iteration  input3 = from, the array of starting indices in each iteration  input4 = to, the array of ending indices in each iteration  input5 = THRESHOLD, the medal count threshold  Output format:  An integer, representing the number of the first officer such that the cumulative sum of medals starting from the first officer upto this officer exceeds THRESHOLD. The output should be -1 if such an officer does not exist.

brain-teasers					A man goes to a hardware shop and asks for price of an item. The shop keeper replies that the item is "one for $1". The man gives the shop keeper "$3 for 600". What did the man buy for his newly painted house?

brain-teasers					Generate all Kaprekar Number (refer Wiki for Kaprekar number's definition) from 1 to 999999.  I gave a brute force approach of generating all number in the range and checking if it is Kaprekar or not.

brain-teasers					Given three points in a 2D plane with their (x, y) coordinates say if the origin lies inside the triangle formed by the three points.

brain-teasers					Given a random generator rand(5) which generates numbers between 0 to 4. How do u generate numbers between 0 to 6, I.e. Implement rand(7).

brain-teasers					Given an excel column number convert it to excel column alphabet and reverse.  Example : If column number(starts from 0) = 26 : Column alpha = AA.

brain-teasers					Two container of 5 L and 3 L are given. Then are is 9.5L water given you need to make 4L water with minimum attempts and water wastage.

brain-teasers					A Contracter is doing work for 7 days at your home, you need to pay him 7000$ in total. Every day you need to pay him 1000$ only .. To Pay him you have a gold plate wortjh 7000$ , but you can cut it only twice

brain-teasers					You have three jars filled with candies. One jar is filled with banana candies, one jar is filled with lemon candies and one jar has a mix of both. All the jars are mislabelled (i.e. all the jars have wrong labels about what kind of candies they contain). All the candies look very similar in shape, size and color and they even smell the same. The only way to distinguish them is by tasting. You have to eat one and only one candy to determine the correct jar labels. You can eat that one candy from any jar you want as long as you eat only one in total.

brain-teasers					What is the minimum representation in bits of two positions on an 8x8 chessboard?

brain-teasers					There is a fictional company called fooBar in fooLand. The CEO of fooBar, fooMan, directs all managers to minimize the total hike that they give to employees, while ensuring that the hike is fair to them. Usually, this is done by giving more hike to employees who are rated better. So, for example, if an employee is rated 2 and is given hike 3x, an employee rated 3 should be given a hike greater than 3x. Hikes are always in multiples of x only and the minimum hike to be given to any employee is x.  This year, however, a wicked manager, barMan comes up with a brilliant strategy. He assumes that each employee would get to know the hike of only the two employees who sit next to him (one on the left, one on the right). And therefore, he reasons(using whole of his analytical left brain), that as long as he could make hikes fair for each employee with respect to the two employees that sit next to him, he would fulfill the dual objective of being "fair" as well as minimizing the total hike given. Just for clarification, the employees of each team sit in one big line.   barMan hires you to calculate the hike to be given to each employee. Over to you. You are supposed to come up with the total hike number that will excite barMan and make him roll on the floor laughing. You are given that no two employee sitting next to each other would have a common rating.  Input:  The order of rating of each employee should be in the order in which they sit. First line will be the value of x. The second line will be the number of employees 'n'. The next 'n' lines specify the rating of each employee. Rating can be integers from 1 to 105. (weird, right?)   1 <= n <= 105. 1 <= x <= 104.  Sample input 1:  10 4 1 4 6 2  Output: 70  Why? If we have the hikes as first employee gets 10, second gets 20, third gets 30 and fourth gets 10, we satisfy all our constraints.

brain-teasers					A lot of transistors contains 0.6 percent defectives. Each transistor is subjected to a test that correctly identifies a defective but also misidentifies as defective about two in every 100 good transistors. Given that a randomly chosen transistor is declared defective by the tester, compute the probability that it is actually defective.

brain-teasers					given a matrix of size m * n, place k students in such a way so that cheating in an exam could be minimized

brain-teasers					Given one egg and a building with infinite number of floors. Find out minimum number of throws at which (least) floor egg will break, if thrown?  I said we have to start at floor 1 and keep incrementing and testing by moving 1 floor up. Then he said optimize it by minimizing no of throws. I could not find more optimal way. I told him that I know with problem with 2 eggs and finite floor building.  Then, he told me that now lets there are 2 eggs and infinite floor building, find minimum no if throws required to find least floor at which egg breaks.  I still could not do that for infinite floors.

brain-teasers					100 doors are closed , In first pass i open all of them , in 2nd pass i toggle every 2nd door , in 3rd pass i toggle every 3rd door , i continue it till 100th pass .. find all the doors that will remain open after 100 passes.

brain-teasers					find the sum of all 4 digit numbers formed from 1 , 2, 3, 4 whithout rep .

brain-teasers					This was the question of two buckets of 3 and 5 litres each. Now measure four litre. I had given 2 solutions but still he wanted 3 solution. 1st soln: fill 3 litre and then interchange in various ways to get 4 litre. 2nd soln: fill 5 litre and then interchange in various ways.   do you have any soln other than this.

brain-teasers					you have a set of integers between 1 .. n in a random order with one of the numbers being repeated. find the best possible way (time and space) to obtain the repeating number.

brain-teasers					4 men- each can cross a bridge in 1,3, 7, and 10 min. Only 2 people can walk the bridge at a time. How many min. minutes would they take to cross the bridge.

brain-teasers					There are two gates , one to hell and the other to heaven. Two gatekeepers , one for each gate. One of them always speaks the truth and the other always lies but you don't know which one s guarding which gate.  You are allowed only one question  and you need to find out the gate to heaven.  What is the question you will ask and remember , you do not know which one speaks the truth and which one lies.

brain-teasers					Find the angle between minute and hour hand when time is 6:50 am

brain-teasers					* You are given 2 eggs. * You have access to a 100-storey building. * Eggs can be very hard or very fragile means it may break if dropped from the first floor or may not even break if dropped from 100 th floor.Both eggs are identical. * You need to figure out the highest floor of a 100-storey building an egg can be dropped without breaking. * Now the question is how many drops you need to make. You are allowed to break 2 eggs in the process.

brain-teasers					Given a dictionary of strings [ strings are in sorted order] you have to find the precedence of characters according to the dictionary.. eat bxy e is ranked above b according to the dictionary.

brain-teasers					How to find min-weight (coin) in a given set of '10' distinct weights (coins) in minimum number of weighing's if provided with a balance. (no labels shown on coin resembling the weight). Generalize for 'n' distinct weights.

brain-teasers					You have a circular track containing fuel pits at irregular intervals. The total amount of fuel available from all the pits together is just sufficient to travel round the track and finish where you started. Given the the circuit perimeter, list of each fuel pit location and the amount of fuel they contain, find the optimal start point on the track such that you never run out of fuel and complete circuit.

brain-teasers					Round 1: Q2: Puzzle Given 25 horses, find the best 3 horses with minimum number of races. Each race can have only 5 horses. You don't have a timer.

brain-teasers					Consider a series in which 8 teams are participating. each team plays twice with all other teams. 4 of them will go to the semi final.How many matches should a team win, so that it will ensure that it will go to semi finals.?

brain-teasers					I applied for the Pricing Quant Internship in Bloomberg and gave the Online Assessment test. I prepared for the Finance and C++ questions but to my very surprise they were all analytical for which I never prepared. Guys if you have applied for the same position please do CAT questions and Reading comprehension.

brain-teasers					I have a lottery ticket. Each of these lottery tickets has a 6 digit number on it. The winning lottery tickets are those whose sum of the first three digits is equal to the sum of the last three digits. How many possible winning tickets are there?  Note: Leading ZEROES are counted. So a number like 004103 is a valid winning ticket since 0+0+4 = 1+0+3.

brain-teasers					There are 100 doors in a row that are all initially closed. You make 100 passes by the doors starting  with the first door every time. The first time through you visit every door and toggle the door  (if the door is closed, you open it, if its open, you close it). The second time you only visit  every 2nd door (door #2, #4, #6). the third time, every 3rd door (door #3, #6, #9), etc, until you  only visit the 100th door. What is the state of each door after the last pass?

brain-teasers					how would you create the index for a book

brain-teasers					Three boxes, one with apples, one with oranges, one with a mix of apples and oranges. all the boxes are labeled incorrectly. you can pick up just one fruit. and tell which box has what fruit.

brain-teasers					Write an algorithm to check the winning condition in a tic-tac toe game for a NXN grid ? (Hint . can be done in O(1) need int ROW[N]; int COL[N]; int diagonal; int anti-diagonal )

brain-teasers					Given 8 cue balls , one is weighing lesser than other 7. Find that(light weight) ball using just 2 chances on balance weight.

brain-teasers					There were 3 racers A, B and C. When A finished the race, B was 8 mts behind A and C was 16 mts behind A. When B finished the race, C was 10 mts behind B. Assuming that three of them ran at constant speed, find the length of the track.

brain-teasers					There are four different treasue chests each one containing gold, silver, brass and copper. There are 100 participants who try to find which chest contains which treasure.  In the end, it appears, that 23 have found none correctly, 58 have only 1 correct and 14 have 2 correct. How many have 3 correct? and how many have 4 correct?

brain-teasers					There are 9 marbles. 8 of them are of equal weight, 1 is not. You are given a weighing scale. How do you find out which one is has the different weight? Is there a faster solution? What is the speed of your solution?

brain-teasers					There are hundred prisoners each standing in a column. Each one is given a hat and there are two possible colors of hat which are red and white. The 100th person can see the hats of 99 people in front of him and the 99th person can see 98 people in front of him but can't see his own and the previous hat. The number of hats aren't known and the hats are placed in random order. Starting with the 100th person, each person is asked what color hat they have.  If they guess wrong, they die.  Come up with a strategy such that maximum people are alive. How many people are alive? (Do not use probability constraint given)

brain-teasers					you have 625 balls on ground and infinite balls in a bag.. make a pyramid from this.. how many balls do you need.. tell structural analysis issues.

brain-teasers					A big cube is made of 1000 small cubes. How many small cubes are there at the surface?

brain-teasers					Given a 3 liter jug and a 5 liter jug, explain how you would measure 4 liters.  He was making it more complex by asking to formulate an equation for that .. was just for stress check..

brain-teasers					Brain teaser. You have 8 coins, only 1 is more heavy. How to detect it

brain-teasers					There are three people who want to know the average of their salary. How can they get the average without disclosing their salary to each other?

brain-teasers					i have number of 10 digits lets sayABCDEFGHIJA represents the number of 0's the above number has,B contains the number of 1's the above number has and so on...Can you find out that number......

brain-teasers					Puzzle:  You've got an 88 checkerboard and a bunch of dominoes that each fit nicely on two squares of the checkboard. You can easily tile the entire checkerboard with these dominoes. Now say that you remove two squares, one at one corner and the other at the opposite corner. You're left with 62 squares. Can you tile this with the dominoes? If so, show how. If not, prove why not.

behavioral					Given two strings, print all the inter-leavings of the Strings in which characters from two strings should be in same order as they were in original strings.  e.g. for "abc", "de", print all of these: adebc, abdec, adbce, deabc, dabce, etc, etc

behavioral					Tell me a time when you took a risk?

behavioral					What do you think is the next big thing in technology? For example, search engine is Google, social media is Facebook, etc. etc...

behavioral					If you are behind the schedule on a project, what will you do? I was asked by multiple interviewers.

behavioral					Why Amazon?

behavioral					 means not. It converts a character to null in a string but converts the character to 0 in an operation 5 means null whereas 5+1=1 Which one of these is true? Cannot recall the options; they all appeared false. I put the last option, but couldnt figure it out. (5)=0?

behavioral					* Why Microsoft? * What is Cloud Computing?  * How would you design a software application? Discussion about software and hardware requirements. How would you handle increase in load? How would you manage the increase in load without additional hardware?

behavioral					why amazon?

behavioral					Prepare a presentation on a project that you believe is the most challenging project that you have undertaken , explain the concept , approach , algorithm .. this presentation lasted for 30 + mins. in which mainly the interviewee does the talking.  Epic is based a lot on luck than skill as in microsoft , amazon and bloomberg... since there would be an HR interview, and a programming test to be done on pen and paper , a quantative test which is simply high school math, a 2 min test on analytical skills , diagrams , series etc, and a test on basic concepts like variables , arrays ...(which is designed for people with non programming back ground).  All my rounds were flawless.. still got a reject.

behavioral					Explain a time when you did not get alogn with something higher managment wanted to implement. How did you handle that?

behavioral					how do you handle the deadlines when there are other important things happening.

behavioral					What keywords would your peers use to describe you, and why?

behavioral					Tell me about a situation where you had to speak up in order to put across a point that was important to you.

behavioral					Describe a time you failed at something. How did you handle it?

behavioral					What interests you least about this job? What did you enjoy least about your last job?

behavioral					What are two positive character traits you don't have?

behavioral					Can you describe a time when you were criticized for your work?

behavioral					Discuss one of the small innovations you made and how it led to solving a real life problem.

behavioral					Give me an example of when you had to go the extra mile to meet a project deadline.

behavioral					What is a time you failed or caused a problem that impacted coworkers or customers?

behavioral					What do you look for in bloomberg? Will you be happy with maintainance work?

behavioral					How do I go about motivating my team?

behavioral					A time where you showed initiative.

behavioral					What part of the software development process do you like most

terminology-trivia					You are given a sorted skewed binary tree. How can you create a binary search tree of minimum height from it?

terminology-trivia					Describe the key differences in NAS and SAN.

terminology-trivia					Tell me the algorithm for fibonacci series? (When i said there are two - recursive (time effcient) and iterative (otherwise)) Explain the recursive one? What is the time complexity? Why is it O(log n)?

terminology-trivia					What is Little Endian and Big endian ?

terminology-trivia					What are memory static variables are created?

terminology-trivia					Phone Interview:The guy who interviewed me is a project leader at Bloomberg. He was very arrogant andhis english was very poor.First he asked me to explain what I have worked on at current company. So I explained him the distributed system I built at world's 3rd best research organization. The discussion went on for 30 minutes and at the end He laughed at it and claimed that its not a real distributed system!He then asked following C++ questions:1. Can you have private destructor and private constructor ? explain your answer.2. Can you have virtual constructor ? explain your answer. 3. What design pattern is similar to virtual constructor ?4. Can you have vector of auto_pointer ? explain your answer.5. is this code valid:   auto_pointer<Object> a(new Object());   auto_pointer<Object> b(new Object());   a = b;  My Answer: Yes its valid ( I checked in the book later)  but he insisted that this is invalid code! what an idiot.If he comes on the phone to interview you, just say "No Thanks!"

terminology-trivia					What is a Singleton class?

terminology-trivia					OO questions: Polymorphism, Inheritance, Encapsulation

trees-and-graphs					Given a Binary tree and value X. Find X in the tree and return its parent  X:           10         4     3    5   7 9   8     If X = 7, return 4

trees-and-graphs					merge two binary search trees

trees-and-graphs					Create a function to calculate the height of an n-ary tree.

trees-and-graphs					Given two (binary) trees, return the first pair of non-matching leaves  Tree 1: A, B, C, D, E, null, null Tree 2: A, D, B  Output: (E,B)

trees-and-graphs					Given a undirected graph with weights, return the sum of the weight of each path between two nodes (shortest path between two vertices). Assume there are no cycles.  Example:

trees-and-graphs					You are given a graph with no cycles, each node representing different cities and there are stadiums for baseball games in all cities.  Each node contains a value representing the population of the city, and a list of neighbors. (feel free to extend data structure)  Every time there is a baseball game at a city, everyone from all the different cities will go to the city with the baseball game.  Return the maximum traffic between a city and its neighbours when there is a game at that city, for all cities. (Does not have to be sorted)   The total run-time after returning everything should be O(n).  Examples:

trees-and-graphs					There are n number of conference rooms available in a company for the meeting. You need to book a meeting for a particular time slot. Write an algorithm to determine the number of conference rooms available for the meeting with given start time and end time. Hint: any conference room with non- overlapping meeting will be selected.

trees-and-graphs					Given the root of a binary tree containing integers, print the columns of the tree in order with the nodes in each column printed top-to-bottom.

trees-and-graphs					Given a forest of balanced binary trees and two nodes, n1 and n2, find the closest common parent of n1 and n2. Nodes have parameters "parent", "left" and "right", and you cannot access the values of the nodes. If n1 and n2 are not on the same tree, return NULL.  Try to do this in O(log(n)) time and O(1) space.

trees-and-graphs					You have a BST and you need to assign an appropriate value to neighbor of all nodes (Explained in below example)            Node Structure

trees-and-graphs					Post order traversal for an N-ary tree iterative way. Given, struct Node {    int val;    vector<Node*> children; };  Without modifying original structure.

trees-and-graphs					Given two binary trees ( not BST) ,   return true if both of them have same inorder  else return false. Eg.

trees-and-graphs					in a tree any root can have any number of children. Every node has an integer value. Find the maximum length on consecutive number sequence anywhere in the tree. For example if root is 2 and one child is 3, its child is 4 its child is 6 then max length will be 3. I was able to write the code the find of one sequence but when one sequence ends and other starts I was not able to handle that case. I think its hard to do by recursion. Is there any other trick or algorithm for this??

trees-and-graphs					design and implement a calculater that can calculate expressions like: + 2 4  * 8 ( + 7 12) ( + 7 ( * 8 12 ) ( * 2 (+ 9 4) 7 ) 3 )  (PS:all items are space delimetered.)  Example answers + 2 4 => 2 + 4 = 6 * 8 ( + 7 12) => 8 * ( 7 + 12 ) = 152 ( + 7 ( * 8 12 ) ( * 2 (+ 9 4) 7 ) 3 ) => 7+8*12+2*(9+4)*7+3 = 148

trees-and-graphs					Design a telephone directory for large ppl (he gave example like design for India). fields will be , first name , last name , number . this should be searchable with first name , last name , number as welll. later added more complexity like do the same for organisation where even it contains designations. so this should be searchable with designations.

trees-and-graphs					Given a self-balancing tree (AVL), code a method that returns the median.  (Median: the numerical value separating the higher half of a data sample from the lower half. Example: if the series is  2, 7, 4, 9, 1, 5, 8, 3, 6  then the median is 5.)

trees-and-graphs					a[] is an array containing elements of a BST . 2D array is given where arr[i][j] gives the root of the tree formed by taking elements from index i to j from a[] . construct the BST .

trees-and-graphs					Disconnect two nodes in a graph by removing minimum number of edges.

trees-and-graphs					Given a Binary Tree (balanced or not) write a method that transforms the tree in a degenerate tree (basically a data structure like a sorted linked list where each node has the left child null) and returns the new root. This must be made in place, no external memory usage is allowed.

trees-and-graphs					One of the many ways of representing a tree is to have an array(of length same as number of nodes), where each element in the node denotes the parent of that node.											  Eg - {-1, 0, 0, 1, 1} would represent a tree with - * 0 as root * 1 and 2 as children of 0 * 3 and 4 as children of 1  Given a similar representation, you have to print reverse level order traversal of the corresponding tree.  Level order traversal of a tree is where we traverse levels of tree one by one.  Eg - For the above given tree, level order traversal would be - 0 1 2 3 4 And hence, the reverse level order traversal is - 3 4 1 2 0 Please note - * An element with parent = -1 is the root element. * An element with the least index becomes the left most child. (ie. a node with always be on left of all its siblings that have higher index than it) * When printing a level of tree you need to maintain left to right order.  Input Format - First line of the input contains number of nodes in the tree (N) Next line contains N (space seperated) numbers that denote where i-th number will denote the parent node of i-th node.  Output Format - Print reverse level order traversal of the corresponding tree, with every new level starting in a different line. Notes/Limits - * 1 <= N <= 50 * There will be only one root element in any given test case * Given numbers will always form a valid undivided tree * Output should be in the exact format as specified (including whitespaces) Sample Test Cases -	 		 Input - 5 -1 0 0 2 1 Output - 4 3 1 2 0  Input - 9 8 7 0 5 5 8 7 0 -1 Output - 1 6 2 7 3 4 0 5 8 Input - 45 24 42 4 30 29 43 22 15 26 36 26 16 3 22 21 41 18 16 34 41 12 29 32 30 43 15 4 38 36 -1 24 42 18 6 21 38 6 17 32 17 3 34 12 14 14 Output - 1 31 20 42 9 28 12 40 33 36 3 23 37 39 6 13 27 35  0 30 11 17 22 38 7 25 5 24 16 32 15 19 8 10 43 44 18 41 2 26 14 34 4 21 29  Input - 33 17 25 0 14 7 2 5 25 18 8 16 27 10 9 19 7 31 31 19 0 8 14 9 17 18 2 30 16 30 10 5 -1 27 Output - 13 22 26 28 4 15 9 20 6 30 1 7 3 21 8 24 5 25 14 18 12 29 11 32 2 19 10 27 0 23 16 17 31

trees-and-graphs					Given a binary tree. Modify it in such a way that after modification you can have a preorder traversal of it using only right pointers. During modification you can use right as well as left pointers. Write complete code and dry run it for some test cases

trees-and-graphs					Question 1 / 3 (Odd even level difference) You are given a function calcDifference which takes in the root pointer of a binary tree as it's input. Complete the function to return the sum of values of nodes at odd height - sum of values of node at even height. Consider the root node is at height 1  Sample Input:  Sample Output -74  Explanation: [ (1 + 4 + 5 + 6 + 7 ) ? (2 + 3 + 8 + 9 + 10 + 11 + 12 + 13  + 14 + 15)   = -74 ]

trees-and-graphs					You are given a grid, with points on the intersections (think a map of streets, people are standing on random corners). Write code to calculate the point on the grid that is the shortest distance from every point on the grid.

trees-and-graphs					We are given a set of integers with repeated occurences of elements. For Example, S={1,2,2}. We need to print the power set of S ensuring that the repeated elements of the power set are printed only once. For the above S, the power set will be {NULL, {1}, {2}, {2}, {1,2}, {1,2}, {2,2}, {1,2,2}}. So, as per the question requirements, we need to print {NULL, {1}, {2}, {1,2}, {2,2}, {1,2,2}}

trees-and-graphs					You are given a sorted skewed binary tree. How can you create a binary search tree of minimum height from it?

trees-and-graphs					A standard chess knight (it moves in its standard way i.e. L shaped OR 2.5 moves) is sitting at the position a1 on an N x N chess board. What is the minimum number of moves it will take to reach the diagonally opposite corner? P.S. - If it were a 8 x 8 chess board, the final destination for the knight would be h8

trees-and-graphs					Given a BST convert it into new Data Structure that satisfies following conditions:  1. every leaf node's left ptr point to its parent and right ptr points to the next leaf 2. every non leaf node's left ptr points to its parent and right ptr is NULL 3. return the head and print the new DS  example:  			7                        /  \                       5   9                      /  \    \                     4   6   10  output:  head->4->5->7         |        ->6->5->7         |         ->10->9-7  with optimal time and space complexity

trees-and-graphs					create the mirror tree for the given BST, provided with the root node of the tree

trees-and-graphs					WAP to create a mirror of a binary tree. Extend the code or write a new code if not possible to do mirroring at alternate levels . Here in the second part , if the two trees are placed in front of each other , then odd levels should be exact mirror as a whole and even levels should be exactly same . Then write the iterative version for the above codes.

trees-and-graphs					Given a family tree for a few generations for the entire population and two people write a routine that will find out if they are blood related.  Siblings are blood related since they have the same parents.  Cousins are blood related since one of their parents have the same parents etc.  Design the data structure first and then write the routine.

trees-and-graphs					Given a binary tree. Print nodes of extreme corners of each level but in alternate order.

trees-and-graphs					Given a binary tree, print its perimeter:  node, left->most nodes from top to bottom, leaf nodes from left-> right, right->most nodes from bottom to top  ----------------------------1 -----------------------2--------3 ------------------4-----5-----6--------7 -------------8------9-----10------11-----12  should print: 1-2-4-8-9-5-10-11-12-7-3  5 because it doesn't have any children. 10 and 11 are children of 6 and 8 & 9 are children of 4.  Apologies for the messy diagram.

trees-and-graphs					Q: Given a binary tree with nodes that have left, right pointers pointing to the left and right children respoectively. It also has a neighbor pointer that currently Points to null. Write a function to make it point to its neighbor.  E.g

trees-and-graphs					Given a binary tree. Write a function that takes only root node as arguement and returns (sum of values at odd height)-(sum of values at even height).

trees-and-graphs					Given  a binary tree return the level with maximum number of nodes

trees-and-graphs					Given a binary tree, find a binary search tree which is a subtree of the given binary tree and has the largest size?  Note : Here size means the no. of nodes and the binary tree can have more than one B.S.T. as its subtree.

trees-and-graphs					Find if the given two trees can be joined leaf to leaf?

trees-and-graphs					Round 3 :  Q 5 : You are given a binary search tree, and a value(data item), you need to tell the left most right cousin in as minimum time and as minimum space ?(need to minimize actual time complexity, he need minimum order of complexity as well as number of node access should be minimum)

trees-and-graphs					two BST are given find common elements in both....

trees-and-graphs					You are a hunter in the forest. A monkey is in the trees, but you don't know where and you can't see it. You can shoot at the trees, you have unlimited ammunition. Immediately after you shoot at a tree, if the monkey was in the tree, he falls and you win. If the monkey was not in the tree, he jumps (randomly) to an adjacent tree (he has to).  Find an algorithm to get the monkey in the fewest shots possible.

trees-and-graphs					Given an array which contains the parent  of the ith element in the n-ary tree.Parent[i] = -1 for root. Find the height of the tree. Gave O(n2) ,space O(1). Expected Complexity- Linear You can use extra space if you want. Example- {-1 0 1 6 6 0 0 2 7}   0  1 2 3 4 5 6 7 8 0 is the root here. 0 is the parent of 1 5 6  1 is parnt of 2 6 is parent of 3 4  2 is of 7 which is parent of 8.

trees-and-graphs					Given a dictionary of strings [ strings are in sorted order] you have to find the precedence of characters according to the dictionary.. eat bxy e is ranked above b according to the dictionary.

trees-and-graphs					Find if a binary tree is bst

trees-and-graphs					Given a  binary tree, find  2 leaf nodes say X and Y  such that F(X,Y) is maximum where F(X,Y) = sum of nodes in the path from root to X + sum of nodes in the path from root to Y - sum of nodes in the common path from root to first common ancestor of the Nodes X and Y

trees-and-graphs					A rooted binary tree with keys in its nodes has the binary search tree  property (BST property) if, for every node, the keys in its left  subtree are smaller than its own key, and the keys in its right  subtree are larger than its own key. It has the heap property if, for  every node, the keys of its children are all smaller than its own key.  You are given a set of n binary tree nodes that each contain an  integer i and an integer j. No two i values are equal and no two j  values are equal. We must assemble the nodes into a single binary tree  where the i values obey the BST property and the j values obey the  heap property. If you pay attention only to the second key in each  node, the tree looks like a heap, and if you pay attention only to the  first key in each node, it looks like a binary search tree.Describe a  recursive algorithm for assembling such a tree

trees-and-graphs					Given a binary tree, compute min depth of a leaf node.  Hint: 1. BFS 2. Recursive implementation Which is better in time complexity?

trees-and-graphs					Give the inorder,postorder& preorder forms of a tree in a single traversal

trees-and-graphs					given a binary tree ,find the largest sub-tree which is a BST...(largest means subtree having largest no of nodes in it)...this is a wonderful question.....

trees-and-graphs					Minimum Common ancestor of given two values in the Binary tree

trees-and-graphs					Reverse a Binary Tree (not BST)  Interviewer started with giving me a sample of balance binary tree with Depth 3 i.e. so total 7 nodes.

trees-and-graphs					Write an algorithm to print a binary tree level wise and that too from leaves to root. Also only one queue and one stack can be used for the purpose.

trees-and-graphs					Given a value and a binary search tree.Print all the paths(if there exists more than one) which sum up to that value. It can be any path in the tree. It doesn't have to be from the root.

trees-and-graphs					If there are two structs, TreeNode and Tree. TreeNode contains 3 elements, data, lChild and rChile. Tree contains 2 elements, int size and TreeNode *root. The tree is a complete tree. So how to find a O(logN) approach to insert a new node.

trees-and-graphs					Algorithm: You have a tree (not Binary) and you want to print the values of all the nodes in this tree level by level. Discussed on phone and asked me to email Java code for my algorithm.

testing					Test Amazon Website Functionalities: Two categories with 100 products each, Buying a product, Customer information, Order tracking

testing					What all Smoke test cases should be performed, if a defect fix is given for a module C. Data will come to module C if its integrated with other Modules say A , B.

testing					There are 6 hosts and there are 6 machines in each host. Admin uses dice role to allocate machine to each user. Write test cases for dice role and machine allocation.

testing					I attended a telephonic round for appstore testing and successfully cleared this round. Following was the First question(apart from tell me abt yourself,etc):  Give me all possible test cases for gmail registration page.

testing					Write down the top ten testcases for sanity check of Templerun app in android based mobile. Testcases should appear in priority order?

testing					Test Google advertisements. Basically the expectation is to get the requirement, assume certain things and come up with test strategies. E.g : UI, Backend, Compatibility, Accessibility etc.  On the fly question were asked

testing					What types of security testing do you know? do you know SQL injections?

testing					How will you test Photo upload feature in facebook, to a Newly created album, to an already existing album, as a standalone photo. Write all negative test cases as well.

testing					Debug Scenarios for : 1. Double Clicking the MP3 File and Nothing happens 2. Double clicking the Player and then playing the file and nothing is heard

testing					How would you test the search functionality on Bing?

testing					You visit a website and it is slow today (it is not slow everyday). What could be the cause(s) of the slowness?

testing					Write all possible test cases for SMS (Short Messaging Service) on a mobile device.

testing					There is an machine which can process any kind of fruit and produce packaged boxes  write test cases for that

testing					Given a string, find the start position of the largest block of repeated charactes.  After the solution, I was asked to write down as many test cases I could to test the function as if it was created by someone else.

testing					Microsoft recruiting final round: Interview 1-Question 2: How would you test an elevator

testing					how will you test if the random number generator is generating actual random numbers

testing					This is one of the interesting questions asked to my friend who had a telephonic with Microsoft recently:  Question: Imagine you have a device that is used to count the number of leaves in a tree. And it has an output screen which displays how many leaves are present in a tree, plus a start/stop button. Write as many test cases as possible and sort them under as different test buckets as possible.

testing					Regression testing,Functional testing and system testing.Explain them and your experience with them?

testing					Write test case for sorting an interger array.This is a simple sort program.

testing					What is metadata? What is the difference between data, meta data and information?

testing					What is the most critical bug you found

testing					Write code and test cases for reversing a C-style string.

testing					Given a canoe, what test cases would you write for it.

testing					This guy asked me about my college, why I am here, what are my long term goals, etc. And then he asked supposed you're on the windows Vista team and there are 5 million programs we have to make sure it works for Vista, but we only have enough resources to test 5000 of them, how do you do it? - This you just have to explain how statistics work and tackling a lot of work by splitting them up and categorizing them.

string-manipulation					Given an input string "aabbccba", find the shortest substring from the alphabet "abc".  In the above example, there are these substrings "aabbc", "aabbcc", "ccba" and "cba". However the shortest substring that contains all the characters in the alphabet is "cba", so "cba" must be the output.  Output doesnt need to maintain the ordering as in the alphabet.  Other examples:  input = "abbcac", alphabet="abc"  Output : shortest substring = "bca".

string-manipulation					You are given a scrambled input sentence. Each word is scrambled independently, and the results are concatenated. So:  'hello to the world' might become: 'elhloothtedrowl'  You have a dictionary with all words in it. Unscramble the sentence.

string-manipulation					Programming Challenge Description:  Develop a service to help a client quickly find a manager who can resolve the conflict between two employees. When there is a conflict between two employees, the closest common manager should help resolve the conflict. The developers plan to test the service by providing an example reporting hierarchy to enable the identification of the closest common manager for two employees. Your goal is to develop an algorithm for IBM to efficiently perform this task. To keep things simple, they just use a single relationship "isManagerOf" between any two employees. For example, consider a reporting structure represented as a set of triples:  Tom isManagerOf Mary Mary isManagerOf Bob Mary isManagerOf Sam Bob isManagerOf John Sam isManagerOf Pete Sam isManagerOf Katie  The manager who should resolve the conflict between Bob and Mary is Tom(Mary's manager). The manager who should resolve the conflict between Pete and Katie is Sam(both employees' manager). The manager who should resolve the conflict between Bob and Pete is Mary(Bob's manager and Pete's manager's manager).   Assumptions: There will be at least one isManagerOf relationship. There can be a maximum of 15 team member to a single manager No cross management would exist i.e., a person can have only one manager There can be a maximum of 100 levels of manager relationships in the corporation  Input:  R1,R2,R3,R4...Rn,Person1,Person2 R1...Rn - A comma separated list of "isManagerOf" relationships. Each relationship being represented by an arrow "Manager->Person". Person1,Person2 - The name of the two employee that have conflict Output:  The name of the manager who can resolve the conflict Note: Please be prepared to provide a video follow-up response to describe your approach to this exercise.  Test 1: Test Input  Frank->Mary,Mary->Sam,Mary->Bob,Sam->Katie,Sam->Pete,Bob->John,Bob,Katie   Expected Output  Mary   Test 2: Test Input  Sam->Pete,Pete->Nancy,Sam->Katie,Mary->Bob,Frank->Mary,Mary->Sam,Bob->John,Sam,John  Expected Output  Mary

string-manipulation					Given an input string and ordering string, need to return true if the ordering string is present in Input string.   input = "hello world!" ordering = "hlo!" result = FALSE (all Ls are not before all Os)  input = "hello world!" ordering = "!od" result = FALSE (the input has '!' coming after 'o' and after 'd', but the pattern needs it to come before 'o' and 'd')  input = "hello world!" ordering = "he!" result = TRUE  input = "aaaabbbcccc" ordering = "ac" result = TRUE

string-manipulation					print all the characters present in the given string only once in a reverse order. Time & Space complexity should not be more than O(N). e.g.  1)Given a string aabdceaaabbbcd the output should be - dcbae  2)Sample String - aaaabbcddddccbbdaaeee  Output - eadbc  3)I/P - aaafffcccddaabbeeddhhhaaabbccddaaaa O/P - adcbhef     Answer :  import java.util.Iterator; import java.util.LinkedHashSet; import java.util.Scanner; import java.util.Set;  public class StringQAmazon { 	public static void main(String args[]) { 		Scanner sc = new Scanner(System.in); 		String inputStr = sc.nextLine(); System.out.println(stringManipulation(inputStr)); 	}  	static String stringManipulation(String str) { 		if(str.isEmpty()) 			return ""; 		else if(str.length()==1) 			return str; 		else { 			str.toLowerCase(); 			StringBuilder strBuilder = new StringBuilder(); 			strBuilder.append(str); 			strBuilder.reverse(); 			Set<Character> set = new LinkedHashSet<Character>(); 			for(int i =0; i<strBuilder.length(); i++){ 				set.add(strBuilder.charAt(i)); 			}  			Iterator<Character> iter = set.iterator(); 			strBuilder=new StringBuilder(); 			while(iter.hasNext()){ 				strBuilder.append(iter.next()); 			}  			return strBuilder.toString();	 		} 		//return null; 	} }

string-manipulation					Given a string e.g. ABCDAABCD. Shuffle he string so that no two smilar letters together. E.g. AABC can be shuffled as ABAC.

string-manipulation					Write 2 functions to serialize and deserialize an array of strings. strings can contain any unicode character. Do not worry about string overflow.

string-manipulation					"Smart substring" Write a function that takes maximum 30 characters from a string but without cutting the words.  Full description: "Featuring stylish rooms and moorings for recreation boats, Room Mate Aitana is a designer hotel built in 2013 on an island in the IJ River in Amsterdam."  First 30 characters: "Featuring stylish rooms and mo"  Smarter approach (max 30 characters, no words are broken): "Featuring stylish rooms and"

string-manipulation					Write program for the following case Reverse string (string is stored in an array) Input:- "This is an example" Output:-sihT si na elpmaxe

string-manipulation					Given a start string, end string and a set of strings, find if there exists a path between the start string and end string via the set of strings.  A path exists if we can get from start string to end string by changing (no addition/removal) only one character at a time. The restriction is that the new string generated after changing one character has to be in the set.  start: "cog"  end: "bad" set: ["bag", "cag", "cat", "fag", "con", "rat", "sat", "fog"] one of the paths: "cog" -> "fog" -> "fag" -> "bag" -> "bad"

string-manipulation					Given a string left rotate it by given number of times with O(n) solution

string-manipulation					We know a string is Palindrome if it is the same reading from both sides. Now we define the following string also Palindrome:  A man, a plan, a canal, Panama!  Write a code that returns if an string is palindrome and  it should return true for above input. (Without directly saying, I should conclude that I have to only consider alphanumerical characters in a string). In addition, we assume the string is very long and we can not keep a copy of this string or even a copy of preprocessed version of this string. Therefore the result should be returned with the first sweep of the string.

string-manipulation					You are tasked with implementing a method that returns the lowest possible number that could be generated after removing n characters from a string of digits. The method signature should look like:

string-manipulation					design and implement a calculater that can calculate expressions like: + 2 4  * 8 ( + 7 12) ( + 7 ( * 8 12 ) ( * 2 (+ 9 4) 7 ) 3 )  (PS:all items are space delimetered.)  Example answers + 2 4 => 2 + 4 = 6 * 8 ( + 7 12) => 8 * ( 7 + 12 ) = 152 ( + 7 ( * 8 12 ) ( * 2 (+ 9 4) 7 ) 3 ) => 7+8*12+2*(9+4)*7+3 = 148

string-manipulation					This question was asked in the chat, just adding here with the solution. I don't know for which company it is.  Replace wild cards with all possible combinations of zeros and ones using recursion.

string-manipulation					Given a string (1-d array) , find if there is any sub-sequence that repeats itself. Here, sub-sequence can be a non-contiguous pattern, with the same relative order.  Eg:   1. abab <------yes, ab is repeated 2. abba <---- No, a and b follow different order  3. acbdaghfb <-------- yes there is a followed by b at two places 4. abcdacb <----- yes a followed by b twice  The above should be applicable to ANY TWO (or every two) characters in the string and optimum over time.  In the sense, it should be checked for every pair of characters in the string.

string-manipulation					Replace %20 with ' '. E.g. input: www.space%20.com 	output: www.space .com

string-manipulation					string x = "1..5,8,11..14,18,20,26..29" string y = "1,2,3,4,5,8,11,12,13,14,18,20,26,27,28,29"  Write a C++ program to expand a given string x to y.

string-manipulation					Given a mapping of alphabets to integers as follows:    1 = A  2 = B  3 = C  ...  26 = Z  Given any combination of the mapping numbers as string, return the number of ways in which the input string can be split into sub-strings  and represented as character strings. For e.g. given  "111" -> "AAA", "AK", "KA" -> 3  Valid combinations are ({1,1,1}, {1,11},{11,1}) = 3  "11" -> "AA", "K" -> 2 Valid combinations are ({1,1},{11}) = 2  "123" -> "ABC", "LC", "AW" -> 3 Valid combinations are ({1,2,3},{1,23},{12,3}) = 3  You don't have to return all the mappings, only the number of valid mappings.

string-manipulation					replace all occurrence of particular word with another word of larger length. Solution should be inplace can do copy only one time. e.g. Gandhi was born in 1969. Gandhi was from gujrat. replace gandhi with mahatma

string-manipulation					You are given a string S and a set of n substrings. You are supposed to remove every instance of those n substrings from S so that S is of the minimum length and output this minimum length. Eg: S- ccdaabcdbb n=2 - substrings-- ab, cd Output: 2 Explanation: ccdaabcdbb -> ccdacdbb -> cabb -> cb (length=2) Can someone help me with the algo?

string-manipulation					Code a function that receives a string composed by words separated by spaces and returns a string where words appear in the same order but than the original string, but every word is inverted. Example, for this input string

string-manipulation					Code a function that gets two strings representing binary numbers (so the only possible characters are '1' and '0', and returns a third string representing the sum of the input. The input strings don't necessarily have of the same length. Tell the complexity of the solution.

string-manipulation					Given three strings str1, str2 and str3; complete the function to find the smallest subsequence in str1 which contains all the characters in str2 (in any order) and not those in str3. Sample Test Case:  Sample Input: str1: spqrstrupvqw str2: sprt str3: q Sample Output: strup Explanation: In the given string str1, the smallest subsequence that contains the characters in str2 ( 's' , 'p' , 'r' , 't' ) and does not contain the character in str3 ( 'q' ) is 'strup'.

string-manipulation					Given two strings a and b, find whether any anagram of string a is a sub-string of string b. For eg:  if a = xyz and b = afdgzyxksldfm then the program should return true.

string-manipulation					Given a set top box: a, b, c, d, e, f, g, h, i, j, k, l, m, n, o p, q, r, s, t u, v, w, x, y z  Write code to give the character sequence given a word, For example, if the word is "CON", the function will print this: Right//now we're at B Right//now we're at C OK//to select C Down DOwn Right Right OK//to select O Left//now at N OK//to select N  note: Be careful when you're at Z. if you go to the right, you will get stuck. Afterwards, the interviewer adds a space to the right of 'Z' to test the code.

string-manipulation					Find Whether a Input string had Palindrome?  Example :  Input Samples : "1234xyzyx5678" ,  "abcdefeabc" Output : A Bool Value, True if Contains a Palindrome , False otherwise. ( In this Example input string conatins "xyzyx"  and efe"  Palindrome respectively)

string-manipulation					input:  "kitten%20pic.jpg" output: "kitten pic.jpg"  %20 -> ' ' %3A -> '?' %3D -> ':'  modify your input in place. no string library functions.  void DecodeURL(string str)

string-manipulation					Find the first non repeating character in a given string. You may assume that the string contains any character from any language in the world, for e.g. an Arabic  or Greek character even.

string-manipulation					Give you two sequences of length N, how to find the max window of matching  patterns. The patterns can be mutated.  For example, seq1 = ABCDEFG, seq2 = DBCAPFG, then the max window is 4. (  ABCD from seq1 and DBCA from seq2).

string-manipulation					Code to check if a given short string is a substring of a main string. Can you get a linear solution (O(n)) if possible?

string-manipulation					Given a string, find the longest possible even palindrome (length of palindrome is even) from it.  Eg:  Input: abcicbbcdefggfed Output: defggfed (length is 8)  Available palindromes are  1) bcicb - has odd length 2) cbbc - even length 3) defggfed - longest palindrome with even length  This question was asked in a telephonic interview for my friend. I will be posting his solution in a day.

string-manipulation					You are given a UNIX path with dot (current) and two dots (parent). Convert this to an absolute path  E.g. $/home/abc/.././def/./ghi/../. becomes $/home/ghi/

string-manipulation					You have a very very big text file.How would you read & process it to print the below output. 1. Print the top ten ranked distinct words. 2. Print the   occurrence of the each alphabet in this file.  For example:  ABC (100) XYZ (40) PQR (10) THE (200) IN (200) Then I have to display the output as IN (200) THE (200)  ABC (100)   XYZ (40). And  A=1000 B=2000 C= 300 .. ... z=300

string-manipulation					Given a string, find whether it has any permutation of another string. For example, given "abcdefg" and "ba", it shuold return true, because "abcdefg" has substring "ab", which is a permutation of "ba".

string-manipulation					Given a string, find the start position of the largest block of repeated charactes.  After the solution, I was asked to write down as many test cases I could to test the function as if it was created by someone else.

string-manipulation					Round 1 : Q 2 : longest palindrome in a string ? (Need to tell in O(n) time complexity + O(1) space complexity)

string-manipulation					Reverse words in a string Ex: Input : "This is a String" Output: "String a is This"

string-manipulation					Given two strings .Print all the interleavings of the two strings. Interleaving means that the if B comes after A .It should also come after A in the interleaved string. ex- AB  and CD ABCD ACBD ACDB CABD CADB CDAB

string-manipulation					Find the substring of length 3 which is present in the reverse order from the string. Ex: if the string is abcdcba (cba is the reverse of abc) so we should return cba. And was asked to improve upon the complexity.

string-manipulation					find if 2 strings are anagrams of each other

string-manipulation					Write a program to reverse a string using recursion?

string-manipulation					find the longest palindrome in a string?

string-manipulation					what is the drawback of strcpy,how can the drawback be fixed

string-manipulation					Write code and test cases for reversing a C-style string.

string-manipulation					Write a function int Compare_Strings(char* str1, char* str2){...} such that the function returns +1, -1 or 0 based on whether str1 is LEXICOGRAPHICALLY greater, smaller or equal to str2; the comparison should be case-insensitive. For example: "abc" is smaller than "mno" as 'a's ASCII value is less than 'm's. However, "ABC" and "abc" are equal. Also discuss the test-cases.

string-manipulation					Write a method to reverse words of string.

string-manipulation					Reverse a string , . don't use any temp variable to store the string .

system-design					Design a service to generate unique 64 bit IDs

system-design					Given that an external service gives a list of credit cards that have become fraud, design a fraud management system for a shopping website for bookings with fraud credit cards

system-design					Design a logging system. The system contains multiple application servers which are logging the information to  file system. In this scenario, we want to check and alarm in case an exception is thrown in any of the servers. We want a system that checks for appearance of specific words, "Error", "Exception", "Disk Full" etc. in the logs of any of the servers. How would you design this system? What if we want to scale the system in future?

system-design					10000 cameras, 100 hours of video each. 30 fps. Police need to input a plate number and find the path of a suspicious vehicle. (Estimate the size of the video, e.g., blueray disc is 2 hours and 20 GB. No need to scan all of the videos. Estimate the time that a vehicle can be seen between 2 traffic cameras, e.g., 0.3 miles and 30 miles per hour, then select 1 out of 100). Web client, load balancer, servers, db.

system-design					How will you design the news feed feature in Facebook?

system-design					This question was asked in the Technical Design round.  How would you design a system to provide the top trending topcis in the last 5m/1hour/24hours The most trending topic should appear first  A topic is said to be trending if it is shared the most. We are talking about a typical multi user environment (something like twitter, facebook).

system-design					Hadoop architecture: How would you deisgn a Craiglist based architecture ? What hadoop components you would use. Given the user can search for a car and the car listings get updated frequently. How would you design the craglist system. What database you would use and how would you process the data ?

system-design					Design the (content) search autocomplete feature on Kindle

system-design					How would you store the relations in a social network like Facebook and implement a feature where one user receives notifications when their friends like the same things as they do?

system-design					Design Facebook Messenger backend

system-design					How would you design the feature in LinkedIn where it computes how many hops there are between you and another person?

system-design					Architect a world-wide video distribution system

system-design					We've 1 book left in the inventory. and two people are trying to get the same book ( say person x and person y ). Person x has added book to the cart and about to make payment and person y has also added book to the cart. How would you solve this concurrency problem ?

system-design					How would you optimize an elevator system for a building with 50 floors and 4 elevators ? Optimize in terms of lowest wait times for the users. Nothing related to power consumption.

system-design					This is design question. Starts with small data size and then goes with bigger data size  Design an application to retrieve the value for a key as fast as possible. The data given to you doesnt change. You are given a data file of 1GB. Its key value data with key being bytes[]. What would be your application design. Now assume the data set is 1 TB or greater how would you change your application design.(Distributed is a possibility).  Now assume the keys are very small. What are your optimizations.

system-design					Design a TinyURL like Service.

system-design					Design software system for a multiplex assuming database server is available - List requirements, DB tables design, APIs. Follow up question how to integrate with third party ticketing systems? how to pass seats availability to ticketing systems?

system-design					I attended a telephonic round for appstore testing and successfully cleared this round. Following was the First question(apart from tell me abt yourself,etc):  Give me all possible test cases for gmail registration page.

system-design					Write a Program for Dictionary which has functionality of lookup and insert . This program should be able to add words on the fly   I wrote simple code using HashTable   follow up   1) Now we are getting too many words what happens  me: Hashtable will dynamically resize resulting into performance hit . Also they might get hashed to same location as well as we might run out of main memory   2) Okay you are out of main memory , How will you scale this program  me: I will create buckets of HashTable lets say 26 buckets for one for each alphabet and would put them on different machines   3) Lets say you are out of memory on those machines too  me: Okay I need to put them on secondary storage . Here we can have fileSystem or Database . I chose database . I will create simple DB schema of BucketNumber and word .   I will use buckets on main memory as cache , if we are not able to find a word in the bucket then query databse with bucket number and words then remove the least number times looked up word (every time we lookup a word we increament the count i.e value in key,value pair on hashtable) from that bucket and add this word .   I mentioned that bottleneck in this case will be every time a word is not present we need to query DB which usually has high latency which will result into performance hit   4) Lets say we are okay with latency but what if we are getting inserting words between that are only between only in two buckets ex. words starting from a and b only.  Now that I think about it, is it better to do this in a trie? What do you guys think?

system-design					How would you synchronize a linked list across multiple computers. If nodes are added/removed to a linked list on one computer, all others must reflect this change. Concurrancy must be accounted for. (java)

system-design					design a system to return an unique ID for each request. For most of requests, the ID value should increase as time goes, the system should handle 1000 requests per second at least. timestamps alone is not valid since there might be multiple requests with same timestamps.

system-design					Given a large network of computers, each keeping log files of visited urls, find the top ten of the most visited urls. (i.e. have many large <string (url) -> int (visits)> maps, calculate implicitly <string (url) -> int (sum of visits among all distributed maps), and get the top ten in the combined map)  The result list must be exact, and the maps are too large to transmit over the network (especially sending all of them to a central server or using MapReduce directly, is not allowed)

system-design					How will you describe iOS manual memory management for a new developer in few words?

system-design					I was asked to design a meeting scheduler, just like in the Microsoft outlook calendar or the gmail calendar. I proposed that I will create an array of 48 for each day. Every 30 min representing the array entry.  I have to make sure that the next appointment does not collide with a previous meeting.  My solution works fine but it wastes too much memory.  Can anyone please tell me how do I find a better solution to detect collision for meetings.  I don't know all the meetings at the beginning. They will be added randomly later.  Thanks,

system-design					Describe the actions performed by two functions: Publish(user, msg) - publishes a new post on behalf of 'user' GetNewsFeed(user) - gathers 30 posts from 'user's friends to show on his/her news feed.  I was asked to map out the relations required for holding large amounts of data.  As a followup, I had to calculate the number of machines facebook would have to initially buy to start off using this news feed.

system-design					You have a bunch of files and folders, Design a playlist which can have any file from any folder and a player that plays it

system-design					Design a realtime service that tells users which of their friends are currently online.  Your service must implement two functions:

system-design					Algorithm: You have 50,000 html files, some of which contain phone numbers. How would you create a list of all the files which contain phone numbers?

database					How would you increase efficiency of a hive query?

database					Suppose that there is a database table, and four processes read the table at the same time. But, only one process is allowed to read the same row of the table at the same time. How do you enforce the exclusive-read on a row?

database					Two tables. Country and City     country --> countryid, country name     city --> countryid, city name      1. how do you get the countries that has no cities?     2. how do you get the countries that has less than 3 cities and also make sure the countries with no cities also show up.

database					I have table with columns (Employee, Manager, Salary).  Need to calculate aggregate salary for all employees corresponding to top-level managers in one SQL. For example  Input table is : Emp   Manager  Salary   A		T	   10   B		A	    11   C		F	     13   D		B	      5   			 		  Result should be : Top-Lvl Manager    Salary(agg) 	T				26 	F				13  Manager-Employee layering can go multiple levels.

database					You have one table with a single column having three values a,b and c. Current snapshot of the table is  Table :- tblTest Values :- tblColumn a a a b b b b c c  We need and output in SQL Server in the format:- Acount  BCount CCount 3           4           2   Do not use temporarytable/variables/multiple queries in a single query.  Values are restricted to be a, b and c only but the count may vary and output will change accordingly.

database					Question Number 1  Consider a table "Student" consisting of columns (Student ID, Student Address, Course).  Every student is allowed to enroll in multiple courses and every course is allowed to enroll more than one student. Also every time a student changes address, all his relevant records must be changed to reflect the new address. What would be the Normal form required to avoid this redundancy?   2nd NF   4th NF   3rd NF   1st NF

database					Which one of the following is NOT a referential integrity issue in a relational database where the DEPT column of the EMPLOYEE table is designated as a foreign key into the DEPARTMENT table?   Updating the value of DEPT in a row of EMPLOYEE with a value that is not the primary key of any of the rows in DEPARTMENT   Inserting a new row into DEPARTMENT with a primary key that is not the value of the DEPT column of any row in EMPLOYEE   Deleting a row of DEPARTMENT   Inserting a new row into EMPLOYEE with a DEPT whose value is not the primary key of any of the rows in DEPARTMENT

computer-architecture-low-level					Design a telephone directory for large ppl (he gave example like design for India). fields will be , first name , last name , number . this should be searchable with first name , last name , number as welll. later added more complexity like do the same for organisation where even it contains designations. so this should be searchable with designations.

computer-architecture-low-level					Could you replace the CPU cache with an SRAM? If you can what would be an advantage and disadvantage

computer-architecture-low-level					You have written a memory manager and after using it your coworker complains that he is facing severe issues of fragmentation. What could be the reason(s) and how can you fix it

computer-architecture-low-level					Describe the design of a low latency distributed environment where multiple processes( or threads) need to access shared data structure or a database for a fast ( speaking of a fraction of a milisecond) read or update. You have to process tons of request very quickly ( you can think of market price data as an example, etc). How would you build such an environment in the most efficient way? Describe the solution in details(a few sentences).

computer-architecture-low-level					What is the difference between a computers heap and it's stack?

computer-architecture-low-level					During boot, after the BIOS performs a successful power-on-self-test, describe everything that occurs until the console is presented to the user.

computer-architecture-low-level					Sequence of steps that happen in CPU, cache, TLB, VM, HDD leading to execution of x = 7 which isnt present in cache or sysmem nor translation in TLB. Also specify if any intrs, exceptions or faults are generated.

computer-architecture-low-level					You have a 64bit interger counter set to 0. How long it will take to overflow the counter given that you are incrementing it at 4Ghz speed

computer-architecture-low-level					Explain how memory allocation works in C++.  Where is the stack vs the heap used?

computer-architecture-low-level					Give me the best way to multiply an integer by 3.5. There are many solutions to this but (x>>1)+x+(x<<1) is the best since it is least prone to overflowing.

computer-architecture-low-level					find number of 1's in particular number fastest way possible. (use hash table).

computer-architecture-low-level					write a macro to give offset of particular field in structure.Like struct abc { int a,int b,char c}. Write a macro like offset(abc , c) to find offset of c from top.

computer-architecture-low-level					If you were to implement a garbage collector in C++ how will you do it?

computer-architecture-low-level					Write an aligned malloc & free function. Which takes number of bytes and aligned byte (which is always power of  2)Ex. align_malloc (1000,128);it will return memory address multiple of 128 of the size 1000.aligned_free(); it will free memory allocated by align_malloc.

computer-architecture-low-level					Can u have a floating point operation inside a interrupt handler?He asked me this question after he asked me whether there can be a print message inside a interrupt handler.

computer-architecture-low-level					For small dataset (less than 200 elements), why is unsorted array has better performance than binary tree? This wasn't the case 20 years ago. (Hint: It has to do with computer architecture.)

computer-architecture-low-level					A disk is partioned into two hemispheres colored in black and white and the disk is rotating.By appropriate positioning of sensors (A sensor can read the disk near it as black or white) we need to find the direction of the motion of the disk.

application-ui-design					How to impliment Google map Data Structure and algorithm.  1. Zoom in/out 2. horizontal/ vertical.  Assumtion - all the image of earth with pixel\Any other assumption is allowed

application-ui-design					How google map implemented ? zoom in , zoom out, moving horizontal and moving vertically. Give data Structure and algorithm. Given all the data from satellite which revolve around earth in spiral way.

application-ui-design					You are asked to code an Android game that shows this board

application-ui-design					I attended a telephonic round for appstore testing and successfully cleared this round. Following was the First question(apart from tell me abt yourself,etc):  Give me all possible test cases for gmail registration page.

application-ui-design					give me the code for : Given a string say "I am a human being" the output should reverse all letters of each word but not the whole string as such. Eg: O/p should be "I ma a namuh gnieb"  I somewhat wrote the code, but i was asked what if there are extra spaces etc. (i am able to write the code sitting at my desktop at one short but there front of interviewer i am struggling. Need to build up my confidence) let me know the best and optimised way of writing this code. Also i suggest people to aviod using inbuilt functions as much as possible    My Answer is as below in perl

application-ui-design					Implement T9 dictionary for mobile phone

application-ui-design					Design the Facebook Credit system which is a application where users can buy/trade virtual currency and can use the virtual currency to purchase Facebook services, like paid apps.

application-ui-design					Implement a read/write lock, given a mutex that has lock() and trylock() interface

application-ui-design					Design the backend for a Gmail-like mail system

application-ui-design					Design a data structure where the following 3 functions are optimised:  1. Insert(n) 2. GetRandomElement() 3. Remove(n)  Write a class, and implement the functions. Give complexity of each of these ..

application-ui-design					Design: How would you design an ATM for the blind

operating-system					What is the following program trying to do?

operating-system					How many times Hello World is printed by following program? int main() {  	if(fork() && fork()) 	{  		fork() 	} 	 if(fork() || fork()) 	{  		fork() 	}  	printf(Hello world) 	return 0 }  a. 16 b. 20 c. 24 d. 64

operating-system					You have written a memory manager and after using it your coworker complains that he is facing severe issues of fragmentation. What could be the reason(s) and how can you fix it

operating-system					You are having a 500 MB RAM and you have a program which uses malloc to allocate 600 MB memory . What will happen , will it be allocated using the concept of virtual memory or not , if yes how?

operating-system					if we open a new tab in a browser,is it a new process or thread?and what if we open a new window of the browser?

operating-system					Does it always happen that stack always grows downwards & heap grows upwards? If its so, then how does OS keeps the heap area protected from the interference of the stack & vice-versa? If its not, then what factors affect it? OS version ? Compiler? Anything else??

operating-system					result of this:

operating-system					Suppose here are n processes in the system and each one needs k instances of a resources to complete. What would be the minimum number of resources that you should keep in the system to ensure no deadlock in the system.]  a.n*k b.n*k-n+1 c.n*k+1 d.n*k*k e.None of the above

operating-system					Given a matrix of integers where every row is sorted and every column is sorted. Print all elements in sorted order.  Cannot use merging of arrays. Solution should be better than O(n2logn)

operating-system					Difference between Spinlock and Mutex. What will you use where?

linked-lists					Write program to print the value of the second last node in a single linked list and write the test cases (code to test) for the same .

linked-lists					Write a program to implement Double Linked List from Stack with min. complexity.

linked-lists					Design a telephone directory for large ppl (he gave example like design for India). fields will be , first name , last name , number . this should be searchable with first name , last name , number as welll. later added more complexity like do the same for organisation where even it contains designations. so this should be searchable with designations.

linked-lists					Consider sorted singly linked list having following nodes  10->30->50->70->NULL  You are given pointer to node 50 and a new node having value 40. Can you inserted node 40 correctly in the list maintaining the ascending order?

linked-lists					Write a function to find 5th element from a singly linked List from the end(not from the head) in one pass.

linked-lists					C program to Delete a node from SLL, in which the last node points to the middle node( in case of even no of nodes, it points to the first middle node) and update the SLL.

linked-lists					Delete last node from the linked list. First node pointer is not given.  I told him its not possible in conventional linked list. He asked me what if we can add some more data in node.  Data should not be a pointer to previous node i.e., it should still be singly linked list.

linked-lists					Write a function which returns kth element from the tail in a linked list.

linked-lists					You have a link list with the following structure: struct Node{ Node*next; Node*other; }  next pointer points to next node, but "other" pointer points to any node in the list, it can be itself or null.  you receive the header of a list with this structure.  you have to copy it(allocate new memory) , you cannot modify the structure, you can not modify the list you are given.

linked-lists					Select a random node data from a very long linked list whose length is not known such that the probability of each node is equal.

linked-lists					How can we reduce search time in linked list(reduce time complexity to O(log n), it is not given but I gave my answer with O(log n) complexity) ?

linked-lists					Given two singly linked list, find if they are intersecting. Do this in single iteration. Also find the intersecting node in O(n) time and O(1) space. By intersection I mean intersection by reference not by value

linked-lists					With a pointer to head node of a linked list as argument, write a function to swap the consecutive elements of the list and return the head node. (Do note change values of any node, only change the links.) Example :- 1->2->3->4->5->6->7 2->1->4->3->6->5->7

linked-lists					You have a circular Linked List: a->b->c->d->e->c Find where the cycle is starting

linked-lists					With a linked list data structure, find if a given string is palindrome or not.

linked-lists					Q1.- Written exam (Amazon, Bangalore)  Given a singly link list and a number 'K', swap the Kth node from the start with the Kth node from the last. Check all the edge cases.  Sample Input: 1->2->3->4->5->6->7->8 and K = 3 Sample Output : 1->2->6->4->5->3->7->8  Sample Input: 1->2->3->4->5->6->7->8 and K = 10 Sample Output: print error "LIST IS OF LESSER SIZE".

linked-lists					Q3. Written Exam Amazon(Bangalore)  Given a singly linked list which may or may not contain loop and loop may or may not start from the head node. Count the number of elements in the linked list.

linked-lists					You are given two numbers in the form of linked list.Add them without reversing the linked lists. linked lists can be of any length. Ex:123 1->2->3 10234 1->0->2->3->4 ans: 10357  1->0->3->5->7

linked-lists					There are two linked lists which converge at one point. Return the 1st node at which they converge

linked-lists					Find the length of a linked list which contains cycle.

linked-lists					List as many data structures as you can think of.  How do you detect a loop in a linked list?

linked-lists					How to delete the kth element from the end of a linked list?

linked-lists					I had first round of phone interview today. She asked me to write two very simple codes in C++ and dictate her as I write. She was also writing the code as I was coding. The questions were:  1. Write code to find nth node (from front) in a linked list. 2. Write code to find minimum node in a BST.  Then test cases for both of these questions. Then the same question which need use of "uniq" command of UNIX.

linux-kernel					What is bottom halves and Top half.? Whats their functionality?

linux-kernel					When is that we we want to use "user virtual address" instead of "kernel virtual address"? List some situations when we cannot go with kernel virtual address.

linux-kernel					As kernel can access user space memory, why should copy_from_user is needed?

linux-kernel					How can one change the value of the Kernel Variables during the runtime?

linux-kernel					Can u have a floating point operation inside a interrupt handler?He asked me this question after he asked me whether there can be a print message inside a interrupt handler.

linux-kernel					How one can measure time spent in context switch.

networking-web-internet					How does traceroute work?

networking-web-internet					Difference between ping and traceroute?

networking-web-internet					What is exactly in an A record?

networking-web-internet					Difference between A record and CName?

networking-web-internet					Difference between Active and Passive FTP?

networking-web-internet					I type www.Amazon.com into the browser and click go, explain in detail what happens?

networking-web-internet					What should not be done in an ISR (Interrupt Service Routine)?

networking-web-internet					Which routing protocol will you use if you have 50 nodes in each area? Choose between OSPF , RIP and explain.

networking-web-internet					There are 10 PC in a network. 9 PC work fine and can open any internet website including google.combut 10th pc in network had a small exception. You can surf any website on that pc but when you try to open google.com its shows page not found error.Whats is the problem on that 10th pc and how you will resolve it ?

networking-web-internet					How to prevent reverse engineering of DLL?

problem-solving					Given an integer array which represents the heights of adjacent vertical bars standing on the ground. The width of each bar is 1. Now you have to pick two bars and remove all the remaining such that when rain falls the water collected between two bars is maximum. Note that the distance between bars remains the same after removing the remaining bars.  eg: 1.  [10,5,6,12,14] ans: 30 (10*3) 2.  [3 16 10 5 6 12 20 18] ans: 80 (16*(number of integers between 16 and 18)).

problem-solving					Given 4 teams and 3 gamedays, create an algorithm such that each team plays another team every gameday and by the end of the 3 game days each team should have played one game with every other team.

problem-solving					Given a sorted array of integers, using the same array, shuffle the integers to have unique elements and return the index.  Sample input : [3, 3, 4, 5, 5, 6, 7, 7, 7] Sample output : [3, 4, 5, 6, 7, X, X, X, X] In this case, it returns an index of 4. The elements in the array after that index is negligible (don't care what value it is).

problem-solving					Find longest substring with "m" unique characters in a given string.  input: aabacbeabbed output:  4 (aaba) for 2 unique characters 6 (aabacb) for 3 unique characters

problem-solving					Create a maze.

problem-solving					design and implement a calculater that can calculate expressions like: + 2 4  * 8 ( + 7 12) ( + 7 ( * 8 12 ) ( * 2 (+ 9 4) 7 ) 3 )  (PS:all items are space delimetered.)  Example answers + 2 4 => 2 + 4 = 6 * 8 ( + 7 12) => 8 * ( 7 + 12 ) = 152 ( + 7 ( * 8 12 ) ( * 2 (+ 9 4) 7 ) 3 ) => 7+8*12+2*(9+4)*7+3 = 148

problem-solving					Design a TinyURL like Service.

problem-solving					Take a list of integers (left to right order) and return an integer of the number of identical binary trees that can be created from the same list.  Input:    [10, 8, 15, 6, 9, 4, 5] Output: 24  Input:    [12, 6, 19, 15, 5] Output: 6  Input:    [44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64] Output: 1  I wrote a brute-force 'solution', creating a binary tree for each permutation of the list (with the same root as Input list) and compared each to the binary tree from the Input list. For large input lists (length > 10), my 'solution' is useless.

problem-solving					Colorful Number: A number can be broken into different sub-sequence parts. Suppose, a number 3245 can be broken into parts like 3 2 4 5 32 24 45 324 245. And this number is a colorful number, since product of every digit of a sub-sequence are different. That is, 3 2 4 5 (3*2)=6 (2*4)=8 (4*5)=20 (3*2*4)= 24 (2*4*5)= 40 But 326 is not a colorful number as it generates 3 2 6 (3*2)=6 (2*6)=12. You have to write a function that tells if the given number is a colorful number or not.

problem-solving					Given a string (1-d array) , find if there is any sub-sequence that repeats itself. Here, sub-sequence can be a non-contiguous pattern, with the same relative order.  Eg:   1. abab <------yes, ab is repeated 2. abba <---- No, a and b follow different order  3. acbdaghfb <-------- yes there is a followed by b at two places 4. abcdacb <----- yes a followed by b twice  The above should be applicable to ANY TWO (or every two) characters in the string and optimum over time.  In the sense, it should be checked for every pair of characters in the string.

problem-solving					Design a telephone directory for large ppl (he gave example like design for India). fields will be , first name , last name , number . this should be searchable with first name , last name , number as welll. later added more complexity like do the same for organisation where even it contains designations. so this should be searchable with designations.

problem-solving					To find loop in a circular linked list, we generally move two pointers , one with speed of one move at a time and other at two at moves at a time. Why do we use ratio 2:1. What can be the best ratio of speed to find a loop in linked list

problem-solving					There is a large file( 1TB) containinig braces. Question is to check for their balance. I said will use a counter, will increment on an open brace and decrement on an close brace. If counter goes negative or counter is non zero at the end of the file, braces are not balanced. Otherwise balanced. Followup question was to make this process parallel ( meaning to see if this problem can be solved through parallelism, like dividing the  the problem into sub problem....)  Remember the file is very large.

problem-solving					5! = 5 * 4 * 3 * 2 * 1 = 120 (it contains 1 zero).    How many zeroes will be contained in 100! then. Explain with logic.

problem-solving					You need to develop the game Snake. What data structures will you use? Code your solution.

problem-solving					Given a sorted array of integers, write a function that will return the number with the biggest number of repetitions.  (Asked to refine the solution to be more efficient)

problem-solving					Given a board made of 2 x n squares, and boards made of 2 x 1 squares, write a function that will calculate the number of possible ways to arrange the 2 x 1 boards on the 2 x n board, in a way that will fill it completely.   (Asked to refine the solution to be more efficient)

problem-solving					You are given a sorted skewed binary tree. How can you create a binary search tree of minimum height from it?

problem-solving					A young girl counted in the following way on the fingers of her left hand. She started calling the thumb 1, the index finger 2, the middle finger 3, the ring finger 4, the little finger 5, then reversed direction calling the ring finger 6, the middle finger 7, the index finger 8, the thumb 9 then back to the index finger for 10, the middle finger for 11, and so on. She counted up to n (to be input by the user). She ended on her which finger?

problem-solving					Implement T9 dictionary for mobile phone

problem-solving					Write a function that finds out if any two numbers within that array add up to a target.

problem-solving					Given an unsorted set of numbers from 1 to 10 with one number missing .  How to find the missing number in the set without sorting. How to find if two numbers are missing in the set?

math-computation					Write function to determine if given unsigned 32-bit number is a power of 3

math-computation					Given 2 large number A and B, create a new number C using the digits from A which needs to be grater than B.  e.g. A = 5281, B = 7443 C = 8125.

math-computation					You are given a bag with N balls (where the value of N is unknown). Each ball in the bag is uniquely numbered with a value between 1 to N (inclusive) i.e. for each number between 1 and N, there is only one ball with that number. Now you pick a ball from the bag and see its number. You repeat this experiment K times. What is the best possible estimate of the value of N (the number of balls in the bag) you can make from the above experiment (of taking out a ball from the bag K times) in the following cases a) With replacement b) Without replacement.

math-computation					You toss a fair coin 400 times. Whats the probability that you get at least 220 heads? Round your answer to the nearest per cent.

math-computation					A bear have to climb a 60.5 feet long hill. It climbs 3 feet in every minute before it fall down for 2 feet. How long it will take to climb the hill?

math-computation					Two dices are tossed. Once die is regular and the other is biased with probabilities P(1) = P(6) = 1/6, P(2) = P(4) = 0, P(3)= P(5) = 1/3.  Determine the probabilities of obtaining the sum  4.

math-computation					Write a method that takes an int as input and outputs an int with the digits of the input in reverse, i.e. 12345 -> 54321.

math-computation					How many squares are present in an NxN grid? In an MxN grid, how many squares are present and how many rectangles?

math-computation					In a book with N pages, pages are numbered from 1 to N. Find out how many times each digit occurs in that book.   You are expected to complete the function getDigitslnBook, which takes an integer as input and  prints how many times each digits occur, one in a line.  The Nth line in the output denotes how many times the integer N-1 occurs in page numbers.  Constrains:    N will be between 1 and 1,000,000,000, inclusive. The output will fit in an integer.  Sample lnputOO: 7  Sample Outputo : 0          1 0 0   Explanation : The page numbers are 1,2, 3,4, 5, 6 and 7.   Sample lnput01: 11  Sample Output01: 1 4             Explanation: Digit 1occurs 4 times, at 1,10 and 11.Rest of the digits occurs only once.

math-computation					How to represent a number in base -2? (negative -2 base) eg 6 can be 11010 i.e. 16 -8 +0 -2 +0 = 6.

math-computation					WAP to sort prime numbers smaller than given N by digits. If N is 40, the output should be 11, 13, 17, 19, 2, 23, 29, 3, 31, 37, 39, 5, 7. Follow-up question: limit memory usage.

math-computation					Formula for nth PI is (-1^n)/(2n+1). Write an efficient way to calculate this.  After i wrote a recursive and iterative solution, she wanted a faster solution. So i went to threading.  Eventually she said that if the value of n is a million and you can't have million threads how will you distribute:  Problem is as n increases the above computation becomes time consuming and hence cannot be simply split in ranges.  She hinted me towards: Queue of jobs, threads picking jobs and en-queuing the work

math-computation					How many  unique words(does not required to have meaning) can you generate from a "EFFICIENT" word

math-computation					Given a function  float convex(float x)  WAP to find the minimum value of convex() between x1 and x2. convex is first monotonically decreasing and then monotonically increasing between x1 and x2.  float minima(float x1, float x2)

math-computation					Given a set of coordinates (x_i, y_i), i ranges from 1 to n, the coordinate values are integers, write a function 'bool isCenterInteger(int points[][])' which returns true if at least one of the midpoints of the line joining the points is an integer.

math-computation					how do you compute the number of digit after . in floating point number. e.g. if given 3.554 output=3 for 43.000 output=0

math-computation					how to divide an integer array into 2 sub-arrays and make their averages equal? e.g. a[left_portion]/left_portion_num == a[right_portion]/right_portion_num.

math-computation					Input an integer array of size n and an integer k (k<=n), output all subsets of size k.

software-design					Design Uber. Low level Design needed (OOPS based - classes, relations, message flow etc.)

software-design					Design a stock market system

software-design					there is a news publishing/subscribing  product of Amazon where electronic contents are collected from owners like newspaper, magazines. Customer is using kindle. Design how customer will get the content when his system kindle connects to net. how to send the contents to device?

software-design					Design a locking mechanism for a distributed system .

software-design					Design Live comments. If your facebook.com homepage is open with bunch of feeds and if someone comments on those feeds, the comments should automatically show up in facebook.com home page without refreshing the page. Feeds could be a simple status update by a friend, post in a group, post by a person you're following, post in a page you've liked etc.   Few things what they are looking for - 1. How do you solve it initially and how do you scale it? 2. How do you scale push model in-case if you choose PUSH model to solve it?  3. If push cannot scale how do you solve it? 4. How pull model solves it? 5. When will you use push vs pull?

software-design					How would you design a price tracking website like camelcamelcamel.com?  For example, we might want the following behavior.  Input: Item URL and target price.  Result: if the item goes below the target price, then users tracking the item will get an email alert.  Consider the following topics in the answer: database design (SQL or NoSQL), automated price checking mechanism, price scraping or price API, caching data.

sql					How would you increase efficiency of a hive query?

sql					Two tables. Country and City     country --> countryid, country name     city --> countryid, city name      1. how do you get the countries that has no cities?     2. how do you get the countries that has less than 3 cities and also make sure the countries with no cities also show up.

sql					I have table with columns (Employee, Manager, Salary).  Need to calculate aggregate salary for all employees corresponding to top-level managers in one SQL. For example  Input table is : Emp   Manager  Salary   A		T	   10   B		A	    11   C		F	     13   D		B	      5   			 		  Result should be : Top-Lvl Manager    Salary(agg) 	T				26 	F				13  Manager-Employee layering can go multiple levels.

sql					Write a SQL to find the nth maximum salary in a employee table.

sorting					Round 6 Question 3 : You are given a word document, you have to print the words with frequencies. Now print the kth rank word in terms of frequency. Print top k words as well by frequencies

sorting					Given a array where each element is maximum +-k index away from it's sorted position, find an algorithm to sort such array.

sorting					{{ There are 3 machines M1, M2 and M3. Each machine is 90% full of its capacity with integers. Now you have to sort all the integers combined and then store the first 1/3rd in M1, second 1/3rd in M2 and last 1/3rd in M3.   Your objective is to minimize the number of sort operations and number of data transfer operations. Each sort operation/data transfer operation is counted as 1 irrespective of the count of values that are being sorted/transferred.  }}

sorting					An efficient way to sort patient files in an array of just 3 types 'High-importance', 'Mid-importance', 'Low-importance' which are in an arbitrary order (unsorted).   The output preference should start with the highest.  1. High-importance   2. Mid-importance  3. Low-importance    [high,low,low,med,high,low]  ps I was told to take advantage of the fact that they are just only 3 types.

sorting					Given a Sorted integer array which is rotated N number of times. You have no idea what that N is. An element in the array can occur more for any number of time. Write a method to search the position of a given element. If there are more than one of the same element, return the position of the first element.

sorting					Given a list of n sorted lists of numbers, write a method that returns one giant list of all the numbers in order.  Example input:  NSArray* input = @[ 				@[@2, @5, @10], 				@[@25, @100, @105], 				@[@7, @56, @42], 					....... 				];

sorting					Write a program for finding a minimum element in rotated sorted array(either ascending or descending ) and array contains duplicates.

sorting					Given a sorted array of integers, write a function that will return the number with the biggest number of repetitions.  (Asked to refine the solution to be more efficient)

sorting					I have 10 million 10-bit integers to sort, how would you sort them and what's the time complexity?   Follow-on question: Instead of sorting integers, I now have 10 million pairs to sort. Each pair consists of a 10-bit integer and an object, the sort order is determined by the 10-bit integer. Will your original sort algorithm hold or do you need sort it differently?  (A word of advice: Ask as many questions as you want during the interview, but you MUST be quick. Also, don't mention anything until you've thought it through clearly, otherwise you're just inviting more questions. Time is of essence, you're too slow if this question takes you more than 15 minutes to come up with the optimal solution, because remember, you have to leave time for explanations and other questions)

sorting					We have n number of sorted array for fixed length. Now we have to merge  these and need to save finaly result array into given array. Note- we can't use extra space except the given array.

sorting					Given an array containing sequence of bits (0 or 1), you have to sort this array in the ascending order i.e. all 0' in first part of array followed by all 1's.   The constraints is that you can swap only the adjacent elements in the array. Find the minimum number of swaps required to sort the given input array.      Example:   Given the array (0,0,1,0,1,0,1,1) the minimum number of swaps is 3.        Note: You just need  to complete the function given  below for this task. The function is given a binary string as input and returns the required answer.

experience					Tell me about another project you have done, how did you do it? what are de difficult parts of it?, tell me everything

experience					This guy asked me about my college, why I am here, what are my long term goals, etc. And then he asked supposed you're on the windows Vista team and there are 5 million programs we have to make sure it works for Vista, but we only have enough resources to test 5000 of them, how do you do it? - This you just have to explain how statistics work and tackling a lot of work by splitting them up and categorizing them.

experience					A time where you showed initiative.

hash-table					Given multiple strings like "candy", "carry", "dummy", etc. These strings are stored as c3y, c3y and d3y etc. Write a function which returns a boolean if the string (like "carry" is unique in the dictionary)   bool isUniqueDictionaryWord(char *str)   If the strings are in a file and you load it when the program loads, how will you store it ?

hash-table					there are numbers in between 0-9999999999 (10-digits) which are assigened someone (does not matter which number assigned who)  Write two methods called "getNumber" and "requestNumber" as follows Number getNumber(); boolean requestNumber(Number number);  getNumber method should find out a number that did not assigened than marks it as assiged and  return that number.  requestNumber method checks the number is assigened or not. If it is assigened returns false, else marks it as assiged and return true.  design a data sturucture to keep those numbers and implement those methods

hash-table					Let's say I gave you a long String and I wanted you to tell me the most common word in that String.  How would you do that?    follow-up: OK, how would you estimate the size and time complexity of this solution?  How would you estimate the ACTUAL size usage?  (Hint: how many words are in the English language?  Would having a dictionary in front of you help?)  follow-up #2: OK, how about if I gave you the entire works of Alexandre Dumas, one of the most prolific authors in history.  How would your solution work?  How could you change it to solve this more specific problem?    follow-up #3: Now, what if we wanted to find the most common PHRASE in his writings.  (Upon clarification, the interviewer wouldn't give a specific length, so I clarified to finding as long as a common 10 word phrase, because anything longer is unlikely.)

hash-table					Design a telephone directory for large ppl (he gave example like design for India). fields will be , first name , last name , number . this should be searchable with first name , last name , number as welll. later added more complexity like do the same for organisation where even it contains designations. so this should be searchable with designations.

hash-table					Find the first non-repeating character in a stream of characters?

hash-table					Consider a hash table with M slots. Suppose hash value is uniformly distributed between 1 to M, and it uses linked list to handle conflicts (if two keys hashed to the same slot). Suppose we put N keys into this M-slotted hash table, what is the probability that there will be a slot with i elements? i could vary from 0 to N.

hash-table					Given an array which contains the parent  of the ith element in the n-ary tree.Parent[i] = -1 for root. Find the height of the tree. Gave O(n2) ,space O(1). Expected Complexity- Linear You can use extra space if you want. Example- {-1 0 1 6 6 0 0 2 7}   0  1 2 3 4 5 6 7 8 0 is the root here. 0 is the parent of 1 5 6  1 is parnt of 2 6 is parent of 3 4  2 is of 7 which is parent of 8.

hash-table					Implement an LRU cache

debugging					How would you increase efficiency of a hive query?

debugging					You have written a memory manager and after using it your coworker complains that he is facing severe issues of fragmentation. What could be the reason(s) and how can you fix it

debugging					Given two arrays of ints that are sets, create a function to merge them to create a new set.  A set must pass on these three conditions: - All values are positive - Sorted - Non-duplicates

unix					What happens when you type in shell

unix					A user creates a file test.sh on a linux system. He wishes to give another user on the same system the permission to execute that file. What permissions should he give to the file?

unix					You are trying to to daemonize an unknown, black-box binary executable.  The binary executable returns no output to STDOUT or STDERR.  Assume that the mystery binary return code is non-zero.  What troubleshooting steps might you take to learn more about what the binary is supposed to do, and why it is failing?

threads					There are 2 threads . How you will synchronize in linux so that 1 thread prints even numbers and other thread prints odd numbers hint: condition variable

threads					Given the two objects below, implement the methods defined in the Phonebook class. This is a simulated phonebook. You should expect LookupByName and LookupByPhoneNumber to be called much more often than AddPerson. Also, this is a multi-threaded simulation so your implementations of the functions other than the constructor should be threadsafe. Feel free to rewrite this in any language of your  choice.

threads					A Multi-threaded server application stops working and the last log message from the application is:

threads					You have 5 data sources. There is a program which calls these data sources and returns a count value.   You need to speedup this program. How do you do that?  This is a sample code

threads					How would you maintain concurrency on a shared page being edited by multiple users simultaneously. What if the page is being shared using a client- server mechanism. Represent the classes and explain the thread safety mechnism to avoid editing conflicts.

threads					Threads synchronization methods, how do they use CPU time slice and compare their efficiency?

threads					Difference between concurrency and parallelism How has threading helped concurrency and parallelism?

threads					Formula for nth PI is (-1^n)/(2n+1). Write an efficient way to calculate this.  After i wrote a recursive and iterative solution, she wanted a faster solution. So i went to threading.  Eventually she said that if the value of n is a million and you can't have million threads how will you distribute:  Problem is as n increases the above computation becomes time consuming and hence cannot be simply split in ranges.  She hinted me towards: Queue of jobs, threads picking jobs and en-queuing the work

threads					You have two threads one printing even numbers in order and other odd numbers. Design an algorithm so that it prints numbers in natural order

threads					If two threads are incrementing a variable 100 times each without synchronization, what would be the possible min and maximum value.

threads					Coding:

threads					Write a multithreaded blocking version of Bounded Queue. There are writers which fill up the queue, and then readers which empty the queue.  If q is full, writer should block. If Q is empty readers should block. The Queue size is finite... (its bounded).  Maximize parallelism, minimize resource usage etc...

threads					result of this:

threads					What's the difference between a thread vs process?

threads					What's the difference between a mutex and a semaphore?