| No. | Title | Mark |
|---|---|---|
| 1 | Two Sum | |
| 3 | Longest Substring Without Repeating Characters | |
| 17 | Letter Combinations of a Phone Number | |
| 30 | Substring with Concatenation of All Words | |
| 41 | First Missing Positive | template |
| 76 | Minimum Window Substring | |
| 105 | Construct Binary Tree from Preorder and Inorder Traversal | |
| 106 | Construct Binary Tree from Inorder and Postorder Traversal | |
| 133 | Clone Graph | |
| 138 | Copy List with Random Pointer | |
| 139 | Word Break | |
| 141 | Linked List Cycle | |
| 142 | Linked List Cycle II | |
| 146 | LRU Cache | |
| 208 | Implement Trie (Prefix Tree) | |
| 264 | Ugly Number II | |
| 340 | Longest Substring with At Most K Distinct Characters | |
| 347 | Top K Frequent Elements | |
| 349 | Intersection of Two Arrays | |
| 438 | Find All Anagrams in a String | |
| 451 | Sort Characters By Frequency | |
| 460 | LFU Cache | |
| 496 | Next Greater Element I | |
| 560 | Subarray Sum Equals K | |
| 567 | Permutation in String | |
| 705 | Design HashSet | design |
| 706 | Design HashMap | design |
| 740 | Delete and Earn | |
| 931 | Maximum Frequency Stack | |
| 1055 | Pairs of Songs With Total Durations Divisible by 60 | |
| 1143 | Find Smallest Common Element in All Rows | |
| 1473 | Find the Longest Substring Containing Vowels in Even Counts |