LeetCode

💻 ✅ Step by step!

LeetCode : https://leetcode.com/

Programming Language : C++

#	Title	Solution	Difficulty
1	Two Sum	1 Two Sum	Easy
2	Add Two Numbers	2 Add Two Numbers	Medium
3	Longest Substring Without Repeating Characters	3 Longest Substring Without Repeating Characters	Medium
4	Median of Two Sorted Arrays	4 Median of Two Sorted Arrays	Hard
5	Longest Palindromic Substring	5 Longest Palindromic Substring	Medium
6	ZigZag Conversion	6 ZigZag Conversion	Medium
7	Reverse Integer	7 Reverse Integer	Easy
8	String to Integer (atoi)	8 String to Integer (atoi)	Medium
9	Palindrome Number	9 Palindrome Number	Easy
10	Regular Expression Matching		Hard
11	Container With Most Water	11 Container With Most Water	Medium
12	Integer to Roman	12 Integer to Roman	Medium
13	Roman to Integer	13 Roman to Integer	Easy
14	Longest Common Prefix	14 Longest Common Prefix	Easy
15	3Sum	15 3Sum	Medium
16	3Sum Closest	16 3Sum Closest	Medium
17	Letter Combinations of a Phone Number	17 Letter Combinations of a Phone Number	Medium
18	4Sum	18 4Sum	Medium
19	Remove Nth Node From End of List	19 Remove Nth Node From End of List	Medium
20	Valid Parentheses	20 Valid Parentheses	Easy
21	Merge Two Sorted Lists	21 Merge Two Sorted Lists	Easy
22	Generate Parentheses	22 Generate Parentheses	Medium
23	Merge k Sorted Lists	23 Merge k Sorted Lists	Hard
25	Reverse Nodes in k-Group	25 Reverse Nodes in k-Group	Hard
26	Remove Duplicates from Sorted Array	26 Remove Duplicates from Sorted Array	Easy
27	Remove Element	27 Remove Element	Easy
31	Next Permutation	31 Next Permutation	Medium
32	Longest Valid Parentheses	32 Longest Valid Parentheses	Hard
33	Search in Rotated Sorted Array	33 Search in Rotated Sorted Array	Medium
34	Find First and Last Position of Element in Sorted Array	34 Find First and Last Position of Element in Sorted Array	Medium
35	Search Insert Position	35 Search Insert Position	Easy
36	Valid Sudoku	36 Valid Sudoku	Medium
39	Combination Sum	39 Combination Sum	Medium
42	Trapping Rain Water	42 Trapping Rain Water	Hard
45	Jump Game II	45 Jump Game II	Hard
46	Permutations	46 Permutations	Medium
48	Rotate Image	48 Rotate Image	Medium
49	Group Anagrams	49 Group Anagrams	Medium
50	Pow(x, n)	50 Pow(x,n)	Medium
53	Maximum Subarray	53 Maximum Subarray	Easy
55	Jump Game	55 Jump Game	Medium
56	Merge Intervals	56 Merge Intervals	Medium
58	Length of Last Word	58 Length of Last Word	Easy
62	Unique Paths	62 Unique Paths	Medium
64	Minimum Path Sum	64 Minimum Path Sum	Medium
66	Plus One	66 Plus One	Easy
67	Add Binary	67 Add Binary	Easy
69	Sqrt(x)	69 Sqrt(x)	Easy
70	Climbing Stairs	70 Climbing Stairs	Easy
72	Edit Distance	72 Edit Distance	Hard
75	Sort Colors	75 Sort Colors	Medium
76	Minimum Window Substring	76 Minimum Window Substring	Hard
78	Subsets	78 Subsets	Medium
79	Word Search	79 Word Search	Medium
84	Largest Rectangle in Histogram	84 Largest Rectangle in Histogram	Hard
85	Maximal Rectangle	85 Maximal Rectangle	Hard
94	Binary Tree Inorder Traversal	94 Binary Tree Inorder Traversal	Medium
96	Unique Binary Search Trees	96 Unique Binary Search Trees	Medium
98	Validate Binary Search Tree	98 Validate Binary Search Tree	Medium
100	Same Tree	100 Same Tree	Easy
101	Symmetric Tree	101 Symmetric Tree	Easy
102	Binary Tree Level Order Traversal	102 Binary Tree Level Order Traversal	Medium
104	Maximum Depth of Binary Tree	104 Maximum Depth of Binary Tree	Easy
105	Construct Binary Tree from Preorder and Inorder Traversal	105 Construct Binary Tree from Preorder and Inorder Traversal	Medium
107	Binary Tree Level Order Traversal II	107 Binary Tree Level Order Traversal II	Easy
111	Minimum Depth of Binary Tree	111 Minimum Depth of Binary Tree	Easy
112	Path Sum	112 Path Sum	Easy
113	Path Sum II	113 Path Sum II	Medium
114	Flatten Binary Tree to Linked List	114 Flatten Binary Tree to Linked List	Medium
118	Pascal's Triangle	118 Pascal's Triangle	Easy
119	Pascal's Triangle II	119 Pascal's Triangle II	Easy
121	Best Time to Buy and Sell Stock	121 Best Time to Buy and Sell Stock	Easy
124	Binary Tree Maximum Path Sum	124 Binary Tree Maximum Path Sum	Hard
128	Longest Consecutive Sequence	128 Longest Consecutive Sequence	Hard
136	Single Number	136 Single Number	Easy
139	Word Break	139 Word Break	Medium
141	Linked List Cycle	141 Linked List Cycle	Easy
142	Linked List Cycle II	142 Linked List Cycle II	Medium
144	Binary Tree Preorder Traversal	144 Binary Tree Preorder Traversal	Medium
145	Binary Tree Postorder Traversal	145 Binary Tree Postorder Traversal	Hard
146	LRU Cache	146 LRU Cache	Medium
148	Sort List	148 Sort List	Medium
151	Reverse Words in a String	151 Reverse Words in a String	Medium
152	Maximum Product Subarray	152 Maximum Product Subarray	Medium
155	Min Stack	155 Min Stack	Easy
160	Intersection of Two Linked Lists	160 Intersection of Two Linked Lists	Easy
169	Majority Element	169 Majority Element	Easy
190	Reverse Bits	190 Reverse Bits	Easy
191	Number of 1 Bits	191 Number of 1 Bits	Easy
198	House Robber	198 House Robber	Easy
199	Binary Tree Right Side View	199 Binary Tree Right Side View	Medium
200	Number of Islands	200 Number of Islands	Medium
201	Bitwise AND of Numbers Range	201 Bitwise AND of Numbers Range	Medium
202	Happy Number	202 Happy Number	Easy
203	Remove Linked List Elements	203 Remove Linked List Elements	Easy
204	Count Primes	204 Count Primes	Easy
205	Isomorphic Strings	205 Isomorphic Strings	Easy
206	Reverse Linked List	206 Reverse Linked List	Easy
207	Course Schedule	207 Course Schedule	Medium
208	Implement Trie (Prefix Tree)	208 Implement Trie (Prefix Tree)	Medium
209	Minimum Size Subarray Sum	209 Minimum Size Subarray Sum	Medium
215	Kth Largest Element in an Array	215 Kth Largest Element in an Array	Medium
217	Contains Duplicate	217 Contains Duplicate	Easy
221	Maximal Square	221 Maximal Square	Medium
222	Count Complete Tree Nodes	222 Count Complete Tree Nodes	Medium
223	Rectangle Area	223 Rectangle Area	Medium
226	Invert Binary Tree	226 Invert Binary Tree	Easy
231	Power of Two	231 Power of Two	Easy
234	Palindrome Linked List	234 Palindrome Linked List	Easy
235	Lowest Common Ancestor of a Binary Search Tree	235 Lowest Common Ancestor of a Binary Search Tree	Easy
236	Lowest Common Ancestor of a Binary Tree	236 Lowest Common Ancestor of a Binary Tree	Medium
237	Delete Node in a Linked List	237 Delete Node in a Linked List	Easy
238	Product of Array Except Self	238 Product of Array Except Self	Medium
239	Sliding Window Maximum	239 Sliding Window Maximum	Hard
240	Search a 2D Matrix II	240 Search a 2D Matrix II	Medium
258	Add Digits	258 Add Digits	Easy
263	Ugly Number	263 Ugly Number	Easy
264	Ugly Number II	264 Ugly Number II	Medium
279	Perfect Squares	279 Perfect Squares	Medium
283	Move Zeroes	283 Move Zeroes	Easy
287	Find the Duplicate Number	287 Find the Duplicate Number	Medium
289	Game of Life	289 Game of Life	Medium
297	Serialize and Deserialize Binary Tree	297 Serialize and Deserialize Binary Tree	Hard
300	Longest Increasing Subsequence	300 Longest Increasing Subsequence	Medium
301	Remove Invalid Parentheses	301 Remove Invalid Parentheses	Hard
309	Best Time to Buy and Sell Stock with Cooldown	309 Best Time to Buy and Sell Stock with Cooldown	Medium
312	Burst Balloons	312 Burst Balloons	Hard
322	Coin Change	322 Coin Change	Medium
337	House Robber III	337 House Robber III	Medium
338	Counting Bits	338 Counting Bits	Medium
344	Reverse String	344 Reverse String	Easy
345	Reverse Vowels of a String	345 Reverse Vowels of a String	Easy
347	Top K Frequent Elements	347 Top K Frequent Elements	Medium
349	Intersection of Two Arrays	349 Intersection of Two Arrays	Easy
371	Sum of Two Integers	371 Sum of Two Integers	Easy
374	Guess Number Higher or Lower	374 Guess Number Higher or Lower	Easy
389	Find the Difference	389 Find the Difference	Easy
394	Decode String	394 Decode String	Medium
399	Evaluate Division	399 Evaluate Division	Medium
401	Binary Watch	401 Binary Watch	Easy
406	Queue Reconstruction by Height	406 Queue Reconstruction by Height	Medium
409	Longest Palindrome	409 Longest Palindrome	Easy
412	Fizz Buzz	412 Fizz Buzz	Easy
416	Partition Equal Subset Sum	416 Partition Equal Subset Sum	Medium
437	Path Sum III	437 Path Sum III	Easy
438	Find All Anagrams in a String	438 Find All Anagrams in a String	Medium
445	Add Two Numbers II	445 Add Two Numbers II	Medium
448	Find All Numbers Disappeared in an Array	448 Find All Numbers Disappeared in an Array	Easy
459	Repeated Substring Pattern	459 Repeated Substring Pattern	Easy
461	Hamming Distance	461 Hamming Distance	Easy
494	Target Sum	494 Target Sum	Medium
501	Find Mode in Binary Search Tree	501 Find Mode in Binary Search Tree	Easy
504	Base 7	504 Base 7	Easy
507	Perfect Number	507 Perfect Number	Easy
509	Fibonacci Number	509 Fibonacci Number	Easy
520	Detect Capital	520 Detect Capital	Easy
530	Minimum Absolute Difference in BST	530 Minimum Absolute Difference in BST	Easy
538	Convert BST to Greater Tree	538 Convert BST to Greater Tree	Easy
541	Reverse String II	541 Reverse String II	Easy
542	01 Matrix	542 01 Matrix	Medium
543	Diameter of Binary Tree	543 Diameter of Binary Tree	Easy
557	Reverse Words in a String III	557 Reverse Words in a String III	Easy
560	Subarray Sum Equals K	560 Subarray Sum Equals K	Medium
561	Array Partition I	561 Array Partition I	Easy
563	Binary Tree Tilt	563 Binary Tree Tilt	Easy
581	Shortest Unsorted Continuous Subarray	581 Shortest Unsorted Continuous Subarray	Easy
594	Longest Harmonious Subsequence	594 Longest Harmonious Subsequence	Easy
606	Construct String from Binary Tree	606 Construct String from Binary Tree	Easy
617	Merge Two Binary Trees	617 Merge Two Binary Trees	Easy
621	Task Scheduler	621 Task Scheduler	Medium
647	Palindromic Substrings	647 Palindromic Substrings	Medium
653	Two Sum IV - Input is a BST	653 Two Sum IV - Input is a BST	Easy
674	Longest Continuous Increasing Subsequence	674 Longest Continuous Increasing Subsequence	uEasy
739	Daily Temperatures	739 Daily Temperatures	Medium
820	Short Encoding of Words	820 Short Encoding of Words	Medium
836	Rectangle Overlap	836 Rectangle Overlap	Easy
876	Middle of the Linked List	876 Middle of the Linked List	Easy
892	Surface Area of 3D Shapes	892 Surface Area of 3D Shapes	Easy
914	X of a Kind in a Deck of Cards	914 X of a Kind in a Deck of Cards	Easy
945	Minimum Increment to Make Array Unique	945 Minimum Increment to Make Array Unique	Medium
974	Subarray Sums Divisible by K	974 Subarray Sums Divisible by K	Medium
999	Available Captures for Rook	999 Available Captures for Rook	Easy
1111	Maximum Nesting Depth of Two Valid Parentheses Strings	1111 Maximum Nesting Depth of Two Valid Parentheses Strings	Medium
1160	Find Words That Can Be Formed by Characters	1160 Find Words That Can Be Formed by Characters	Easy
1248	Count Number of Nice Subarrays	1248 Count Number of Nice Subarrays	Medium
1431	Kids With the Greatest Number of Candies	1431 Kids With the Greatest Number of Candies	Easy