| 12. Integer to Roman | | | Solve | Medium | | |
| 15. 3Sum | | | Solve | Medium | | |
| 31. Next Permutation | | | Solve | Medium | | |
| 33. Search in Rotated Sorted Array | | | Solve | Medium | | |
| 45. Jump Game II | | | Solve | Medium | | |
| 49. Group Anagrams | | | Solve | Medium | | |
| 50. Pow(x, n) | | | Solve | Medium | | |
| 56. Merge Intervals | | | Solve | Medium | | |
| 59. Spiral Matrix II | | | Solve | Medium | | |
| 93. Restore IP Addresses | | | Solve | Medium | | |
| 98. Validate Binary Search Tree | | | Solve | Medium | | |
| 130. Surrounded Regions | | | Solve | Medium | | |
| 131. Palindrome Partitioning | | | Solve | Medium | | |
| 134. Gas Station | | | Solve | Medium | | |
| 146. LRU Cache | | | Solve | Medium | | |
| 200. Number of Islands | | | Solve | Medium | | |
| 204. Count Primes | | | Solve | Medium | | |
| 207. Course Schedule | | | Solve | Medium | | |
| 210. Course Schedule II | | | Solve | Medium | | |
| 215. Kth Largest Element in an Array | | | Solve | Medium | | |
| 259. 3Sum Smaller | | | Solve | Medium | | |
| 286. Walls and Gates | | | Solve | Medium | | |
| 300. Longest Increasing Subsequence | | | Solve | Medium | | |
| 316. Remove Duplicate Letters | | | Solve | Medium | | |
| 328. Odd Even Linked List | | | Solve | Medium | | |
| 353. Design Snake Game | | | Solve | Medium | | |
| 386. Lexicographical Numbers | | | Solve | Medium | | |
| 394. Decode String | | | Solve | Medium | | |
| 399. Evaluate Division | | | Solve | Medium | | |
| 437. Path Sum III | | | Solve | Medium | | |
| 486. Predict the Winner | | | Solve | Medium | | |
| 487. Max Consecutive Ones II | | | Solve | Medium | | |
| 503. Next Greater Element II | | | Solve | Medium | | |
| 523. Continuous Subarray Sum | | | Solve | Medium | | |
| 556. Next Greater Element III | | | Solve | Medium | | |
| 560. Subarray Sum Equals K | | | Solve | Medium | | |
| 658. Find K Closest Elements | | | Solve | Medium | | |
| 670. Maximum Swap | | | Solve | Medium | | |
| 722. Remove Comments | | | Solve | Medium | | |
| 735. Asteroid Collision | | | Solve | Medium | | |
| 787. Cheapest Flights Within K Stops | | | Solve | Medium | | |
| 791. Custom Sort String | | | Solve | Medium | | |
| 799. Champagne Tower | | | Solve | Medium | | |
| 856. Score of Parentheses | | | Solve | Medium | | |
| 886. Possible Bipartition | | | Solve | Medium | | |
| 919. Complete Binary Tree Inserter | | | Solve | Medium | | |
| 945. Minimum Increment to Make Array Unique | | | Solve | Medium | | |
| 946. Validate Stack Sequences | | | Solve | Medium | | |
| 947. Most Stones Removed with Same Row or Column | | | Solve | Medium | | |
| 981. Time Based Key-Value Store | | | Solve | Medium | | |