| 1 | Two Sum | Read solution |
| 2 | Longest Palindromic Substring | Read solution |
| 3 | 3Sum | Read solution |
| 4 | Merge Two Sorted Lists | Read solution |
| 5 | Merge k Sorted Lists | Read solution |
| 6 | Trapping Rain Water | Read solution |
| 7 | Group Anagrams | Read solution |
| 8 | Maximum Subarray | Read solution |
| 9 | Word Search | Read solution |
| 10 | Binary Tree Zigzag Level Order Traversal | Read solution |
| 11 | Best Time to Buy and Sell Stock | Read solution |
| 12 | Word Ladder II | — |
| 13 | Word Ladder | — |
| 14 | Copy List with Random Pointer | Read solution |
| 15 | Word Break | Read solution |
| 16 | Word Break II | Read solution |
| 17 | LRU Cache | Read solution |
| 18 | Min Stack | Read solution |
| 19 | Number of Islands | Read solution |
| 20 | Course Schedule II | Read solution |
| 21 | Word Search II | Read solution |
| 22 | Basic Calculator II | — |
| 23 | Sliding Window Maximum | Read solution |
| 24 | Search a 2D Matrix II | — |
| 25 | Meeting Rooms II | — |
| 26 | Alien Dictionary | — |
| 27 | Integer to English Words | — |
| 28 | Find Median from Data Stream | Read solution |
| 29 | Serialize and Deserialize Binary Tree | Read solution |
| 30 | Design Snake Game | — |
| 31 | Insert Delete GetRandom O 1 | — |
| 32 | LFU Cache | Read solution |
| 33 | Concatenated Words | — |
| 34 | Subtree of Another Tree | — |
| 35 | Design In-Memory File System | — |
| 36 | Design Search Autocomplete System | — |
| 37 | Top K Frequent Words | Read solution |
| 38 | Number of Distinct Islands | — |
| 39 | Partition Labels | — |
| 40 | Most Common Word | Read solution |
| 41 | All Nodes Distance K in Binary Tree | — |
| 42 | Snakes and Ladders | — |
| 43 | Reorder Data in Log Files | — |
| 44 | Prison Cells After N Days | — |
| 45 | K Closest Points to Origin | Read solution |
| 46 | Rotting Oranges | Read solution |
| 47 | Analyze User Website Visit Pattern | — |
| 48 | Minimum Cost to Connect Sticks | — |
| 49 | Critical Connections in a Network | — |
