| 1. Two Sum | Solution | Solve | Easy | | |
| 3. Longest Substring Without Repeating Characters | Solution | Solve | Medium | | |
| 6. Zigzag Conversion | Solution | Solve | Medium | | |
| 15. 3Sum | Solution | Solve | Medium | | |
| 20. Valid Parentheses | Solution | Solve | Easy | | |
| 22. Generate Parentheses | Solution | Solve | Medium | | |
| 31. Next Permutation | Solution | Solve | Medium | | |
| 32. Longest Valid Parentheses | Solution | Solve | Hard | | |
| 37. Sudoku Solver | Solution | Solve | Hard | | |
| 49. Group Anagrams | Solution | Solve | Medium | | |
| 54. Spiral Matrix | Solution | Solve | Medium | | |
| 56. Merge Intervals | Solution | Solve | Medium | | |
| 66. Plus One | Solution | Solve | Easy | | |
| 85. Maximal Rectangle | Solution | Solve | Hard | | |
| 91. Decode Ways | Solution | Solve | Medium | | |
| 121. Best Time to Buy and Sell Stock | Solution | Solve | Easy | | |
| 125. Valid Palindrome | Solution | Solve | Easy | | |
| 139. Word Break | Solution | Solve | Medium | | |
| 146. LRU Cache | Solution | Solve | Medium | | |
| 155. Min Stack | Solution | Solve | Medium | | |
| 198. House Robber | Solution | Solve | Medium | | |
| 207. Course Schedule | Solution | Solve | Medium | | |
| 210. Course Schedule II | Solution | Solve | Medium | | |
| 215. Kth Largest Element in an Array | Solution | Solve | Medium | | |
| 236. Lowest Common Ancestor of a Binary Tree | Solution | Solve | Medium | | |
| 238. Product of Array Except Self | Solution | Solve | Medium | | |
| 283. Move Zeroes | Solution | Solve | Easy | | |
| 295. Find Median from Data Stream | Solution | Solve | Hard | | |
| 300. Longest Increasing Subsequence | Solution | Solve | Medium | | |
| 322. Coin Change | Solution | Solve | Medium | | |
| 347. Top K Frequent Elements | Solution | Solve | Medium | | |
| 354. Russian Doll Envelopes | Solution | Solve | Hard | | |
| 359. Logger Rate Limiter | Solution | Solve | Easy | | |
| 380. Insert Delete GetRandom O(1) | Solution | Solve | Medium | | |
| 394. Decode String | Solution | Solve | Medium | | |
| 443. String Compression | Solution | Solve | Medium | | |
| 456. 132 Pattern | Solution | Solve | Medium | | |
| 493. Reverse Pairs | Solution | Solve | Hard | | |
| 503. Next Greater Element II | Solution | Solve | Medium | | |
| 622. Design Circular Queue | Solution | Solve | Medium | | |
| 628. Maximum Product of Three Numbers | Solution | Solve | Easy | | |
| 647. Palindromic Substrings | Solution | Solve | Medium | | |
| 664. Strange Printer | Solution | Solve | Hard | | |
| 673. Number of Longest Increasing Subsequence | Solution | Solve | Medium | | |
| 678. Valid Parenthesis String | Solution | Solve | Medium | | |
| 695. Max Area of Island | Solution | Solve | Medium | | |
| 739. Daily Temperatures | Solution | Solve | Medium | | |
| 759. Employee Free Time | Solution | Solve | Hard | | |
| 770. Basic Calculator IV | Solution | Solve | Hard | | |
| 787. Cheapest Flights Within K Stops | Solution | Solve | Medium | | |
