171 problems
| Problem | Difficulty | Frequency ↓ | Topics |
|---|---|---|---|
| 323. Number of Connected Components in an Undirected Graph | Medium | 42.6% | TopicsDepth-First SearchBreadth-First SearchUnion-FindGraph Theory |
| Sqrt(x) | Easy | 42.6% | TopicsMathBinary SearchNewton's Method |
| Find K Closest Elements | Medium | 39.8% | TopicsArrayTwo PointersBinary SearchSliding WindowSortingHeap (Priority Queue) |
| 695. Max Area of Island | Medium | 39.8% | TopicsArrayDepth-First SearchBreadth-First SearchUnion-FindMatrix |
| Paint House II | Hard | 39.8% | TopicsArrayDynamic Programming |
| Valid Triangle Number | Medium | 36.5% | TopicsArrayTwo PointersBinary SearchGreedySorting |
| 40. Combination Sum II | Medium | 36.5% | TopicsArrayBacktracking |
| 678. Valid Parenthesis String | Medium | 36.5% | TopicsStringDynamic ProgrammingStackGreedyBracket Sequences |
| Longest Valid Parentheses | Hard | 36.5% | TopicsStringDynamic ProgrammingStackBracket Sequences |
| Smallest Range Covering Elements from K Lists | Hard | 36.5% | TopicsArrayHash TableGreedySliding WindowSortingHeap (Priority Queue) |
| Reverse Words in a String | Medium | 36.5% | TopicsTwo PointersString |
| 3. Longest Substring Without Repeating Characters | Medium | 32.4% | TopicsHash TableStringSliding Window |
| 100. Same Tree | Easy | 32.4% | TopicsTreeDepth-First SearchBreadth-First SearchBinary Tree |
| Word Ladder II | Hard | 32.4% | TopicsHash TableStringBacktrackingBreadth-First SearchBidirectional Search |
| 155. Min Stack | Medium | 32.4% | TopicsStackDesign |
| Shuffle an Array | Medium | 32.4% | TopicsArrayMathDesignRandomized |
| 706. Design HashMap | Easy | 32.4% | TopicsArrayHash TableLinked ListDesignHash Function |
| Number of Divisible Triplet Sums | Medium | 32.4% | TopicsArrayHash Table |
| Delete Node in a BST | Medium | 32.4% | TopicsTreeBinary Search TreeBinary Tree |
| 1386. Cinema Seat Allocation | Medium | 32.4% | TopicsArrayHash TableGreedyBit Manipulation |
| 1882. Process Tasks Using Servers | Medium | 32.4% | TopicsArrayHeap (Priority Queue) |
| LFU Cache | Hard | 32.4% | TopicsHash TableLinked ListDesignDoubly-Linked List |
| 12. Integer to Roman | Medium | 27.3% | TopicsHash TableMathString |
| 39. Combination Sum | Medium | 27.3% | TopicsArrayBacktracking |
| 213. House Robber II | Medium | 27.3% | TopicsArrayDynamic Programming |
