| 56. Merge Intervals | | | Solve | Medium | | |
| 78. Subsets | | | Solve | Medium | | |
| 79. Word Search | | | Solve | Medium | | |
| 124. Binary Tree Maximum Path Sum | | | Solve | Hard | | |
| 208. Implement Trie (Prefix Tree) | | | Solve | Medium | | |
| 212. Word Search II | | | Solve | Hard | | |
| 239. Sliding Window Maximum | | | Solve | Hard | | |
| 256. Paint House | | | Solve | Medium | | |
| 295. Find Median from Data Stream | | | Solve | Hard | | |
| 332. Reconstruct Itinerary | | | Solve | Hard | | |
| 341. Flatten Nested List Iterator | | | Solve | Medium | | |
| 358. Rearrange String k Distance Apart | | | Solve | Hard | | |
| 362. Design Hit Counter | | | Solve | Medium | | |
| 380. Insert Delete GetRandom O(1) | | | Solve | Medium | | |
| 433. Minimum Genetic Mutation | | | Solve | Medium | | |
| 453. Minimum Moves to Equal Array Elements | | | Solve | Medium | | |
| 528. Random Pick with Weight | | | Solve | Medium | | |
| 580. Count Student Number in Departments | | | Solve | Medium | | |
| 585. Investments in 2016 | | | Solve | Medium | | |
| 586. Customer Placing the Largest Number of Orders | | | Solve | Easy | | |
| 608. Tree Node | | | Solve | Medium | | |
| 635. Design Log Storage System | | | Solve | Medium | | |
| 642. Design Search Autocomplete System | | | Solve | Hard | | |
| 647. Palindromic Substrings | | | Solve | Medium | | |
| 721. Accounts Merge | | | Solve | Medium | | |
| 831. Masking Personal Information | | | Solve | Medium | | |
| 868. Binary Gap | | | Solve | Easy | | |
| 895. Maximum Frequency Stack | | | Solve | Hard | | |
| 921. Minimum Add to Make Parentheses Valid | | | Solve | Medium | | |
| 1206. Design Skiplist | | | Solve | Hard | | |
| 1326. Minimum Number of Taps to Open to Water a Garden | | | Solve | Hard | | |
| 1347. Minimum Number of Steps to Make Two Strings Anagram | | | Solve | Medium | | |
| 1348. Tweet Counts Per Frequency | | | Solve | Medium | | |
| 1459. Rectangles Area | | | Solve | Medium | | |
| 1683. Invalid Tweets | | | Solve | Easy | | |
| 1751. Maximum Number of Events That Can Be Attended II | | | Solve | Hard | | |
| 1785. Minimum Elements to Add to Form a Given Sum | | | Solve | Medium | | |
| 1797. Design Authentication Manager | | | Solve | Medium | | |
| 1817. Finding the Users Active Minutes | | | Solve | Medium | | |
| 1868. Product of Two Run-Length Encoded Arrays | | | Solve | Medium | | |
| 1882. Process Tasks Using Servers | | | Solve | Medium | | |
| 1905. Count Sub Islands | | | Solve | Medium | | |
| 2073. Time Needed to Buy Tickets | | | Solve | Easy | | |
| 2768. Number of Black Blocks | | | Solve | Medium | | |
