2324 problems
| Problem | Difficulty | Frequency ↓ | Topics |
|---|---|---|---|
| 1. Two Sum | Easy | 100% | TopicsArrayHash Table |
| 2. Add Two Numbers | Medium | 78.6% | TopicsLinked ListMathRecursion |
| 4. Median of Two Sorted Arrays | Hard | 74.3% | TopicsArrayBinary SearchDivide and Conquer |
| 14. Longest Common Prefix | Easy | 73.8% | TopicsArrayStringTrie |
| 9. Palindrome Number | Easy | 73.8% | TopicsMath |
| 42. Trapping Rain Water | Hard | 73.5% | TopicsArrayTwo PointersDynamic ProgrammingStackMonotonic Stack |
| 3Sum | Medium | 72.8% | TopicsArrayTwo PointersSorting |
| 3. Longest Substring Without Repeating Characters | Medium | 72.6% | TopicsHash TableStringSliding Window |
| 121. Best Time to Buy and Sell Stock | Easy | 71.9% | TopicsArrayDynamic Programming |
| Longest Consecutive Sequence | Medium | 70.8% | TopicsArrayHash TableUnion-Find |
| 5. Longest Palindromic Substring | Medium | 69.4% | TopicsTwo PointersStringDynamic ProgrammingManacher |
| 88. Merge Sorted Array | Easy | 69.2% | TopicsArrayTwo PointersSorting |
| 11. Container With Most Water | Medium | 68.4% | TopicsArrayTwo PointersGreedy |
| 20. Valid Parentheses | Easy | 67.4% | TopicsStringStackBracket Sequences |
| 1768. Merge Strings Alternately | Easy | 67% | TopicsTwo PointersString |
| 169. Majority Element | Easy | 66.6% | TopicsArrayHash TableDivide and ConquerSortingCountingBoyer–Moore Majority Vote Algorithm |
| Create Hello World Function | Easy | 66.3% | Topics— |
| 7. Reverse Integer | Medium | 66.3% | TopicsMath |
| 560. Subarray Sum Equals K | Medium | 65.8% | TopicsArrayHash TablePrefix Sum |
| Remove Duplicates from Sorted Array | Easy | 65.7% | TopicsArrayTwo Pointers |
| 13. Roman to Integer | Easy | 65.1% | TopicsHash TableMathString |
| 53. Maximum Subarray | Medium | 64.8% | TopicsArrayDivide and ConquerDynamic Programming |
| 56. Merge Intervals | Medium | 64.8% | TopicsArraySortingQuicksort |
| 200. Number of Islands | Medium | 64.1% | TopicsArrayDepth-First SearchBreadth-First SearchUnion-FindMatrix |
| Recyclable and Low Fat Products | Easy | 63.8% | TopicsDatabase |
