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BINARY TREE PROBLEM

Imagine a binary tree like below:

      1
  2	   3
4   5    6   7

Given a node in this tree, a sum of its subsequents nodes is required to be calculated.

Examples

• Node 2:

4 + 5 = 9

• Node 3:

6 + 7 = 13

• Node 4:

0 

As there is no node under node 4.

Solution

br/com/buzachero/BinaryTree.java

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NUMBER CALCULATION PROBLEM

Given two numbers A and B, a number C is required, but the following assumptions must be attended:

• 1st digit of number A is the 1st digit of number C;

• 1st digit of number B is the 2nd digit of number C;

• 2nd digit of number A is the 3rd digit of number C;

• 2nd digit of number B is the 4th digit of number C;

• and so on...

• If one of the number has higher amount of digits, so the surplus digits should be copied to number C

• If output of number C is greater than 1000000, so the value of number C is -1

Examples

• Example 1

number A = 1245
number B = 1111
number C = 11214151 > 1000000

Therefore:

number C = -1

• Example 2

number A = 58
number B = 1478
number C = 518478 ( < 1000000)

Solution

br/com/buzachero/Calculator.java

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MATRIX DIFFERENCE OF SUM DIAGONALS CALCULATION PROBLEM

Given a matrix N x N, it is required to calculate the difference between the sum of its diagonal.

Example

Matrix = 
[ 1, 2, 3
  4, 5, 6, 
  7, 8, 9 ]
 Diagonal1 : 1 + 5 + 9 = 15
 Diagonal2 : 3 + 5 + 7 = 15
 Difference = Diagonal1 - Diagonal2
 Difference = 0

Solution

br/com/buzachero/Matrix.java 

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ELETRONICS SHOP

Given two arrays of prices, one for keyboards and another one for USB drive, and a budget to spend on these items, it is required to calculate the maximum money to spend.

Example

keyboard prices = [3 1]
USB drives prives = [5 2 8]
budget = 10
Max money to spend = 9

Solution

br/com/buzachero/EletronicsShop.java

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CATS AND MOUSE

Given:

1. Cat A position x;
2. Cat B position y;
3. Mouse C position z;

Determine which cat will take the mouse first.

• If cat A arrives first, print "Cat A";
• If cat B arrives first, print "Cat B";
• If both cats arrive at the same time, print "Mouse C".