All companiesTwitter
8 Easy31 Medium12 Hard51 total
| No. | Problem | Difficulty | Frequency |
|---|---|---|---|
| 10 | Regular Expression Matching | Hard | |
| 12 | Integer to Roman | Medium | |
| 20 | Valid Parentheses | Easy | |
| 23 | Merge k Sorted Lists | Hard | |
| 42 | Trapping Rain Water | Hard | |
| 43 | Multiply Strings | Medium | |
| 44 | Wildcard Matching | Hard | |
| 56 | Merge Intervals | Medium | |
| 60 | Permutation Sequence | Hard | |
| 118 | Pascal's Triangle | Easy | |
| 140 | Word Break II | Hard | |
| 146 | LRU Cache | Medium | |
| 2073 | Time Needed to Buy Tickets | Easy | |
| 149 | Max Points on a Line | Hard | |
| 161 | One Edit Distance | Medium | |
| 202 | Happy Number | Easy | |
| 206 | Reverse Linked List | Easy | |
| 208 | Implement Trie (Prefix Tree) | Medium | |
| 218 | The Skyline Problem | Hard | |
| 235 | Lowest Common Ancestor of a Binary Search Tree | Medium | |
| 251 | Flatten 2D Vector | Medium | |
| 269 | Alien Dictionary | Hard | |
| 296 | Best Meeting Point | Hard | |
| 1206 | Design Skiplist | Hard | |
| 323 | Number of Connected Components in an Undirected Graph | Medium | |
| 341 | Flatten Nested List Iterator | Medium | |
| 355 | Design Twitter | Medium | |
| 378 | Kth Smallest Element in a Sorted Matrix | Medium | |
| 380 | Insert Delete GetRandom O(1) | Medium | |
| 407 | Trapping Rain Water II | Hard | |
| 433 | Minimum Genetic Mutation | Medium | |
| 1347 | Minimum Number of Steps to Make Two Strings Anagram | Medium | |
| 1348 | Tweet Counts Per Frequency | Medium | |
| 468 | Validate IP Address | Medium | |
| 580 | Count Student Number in Departments | Medium | |
| 1459 | Rectangles Area | Medium | |
| 585 | Investments in 2016 | Medium | |
| 586 | Customer Placing the Largest Number of Orders | Easy | |
| 608 | Tree Node | Medium | |
| 1683 | Invalid Tweets | Easy | |
| 2768 | Number of Black Blocks | Medium | |
| 831 | Masking Personal Information | Medium | |
| 1797 | Design Authentication Manager | Medium | |
| 1785 | Minimum Elements to Add to Form a Given Sum | Medium | |
| 868 | Binary Gap | Easy | |
| 1817 | Finding the Users Active Minutes | Medium | |
| 1882 | Process Tasks Using Servers | Medium | |
| 1910 | Remove All Occurrences of a Substring | Medium | |
| 1905 | Count Sub Islands | Medium | |
| 764 | Largest Plus Sign | Medium | |
| 1167 | Minimum Cost to Connect Sticks | Medium |