Millennium
10 problems
| Problem | Difficulty | Frequency ↓ | Topics |
|---|---|---|---|
| 121. Best Time to Buy and Sell Stock | Easy | 100% | TopicsArrayDynamic Programming |
| 2484. Count Palindromic Subsequences | Hard | 100% | TopicsStringDynamic Programming |
| 2603. Collect Coins in a Tree | Hard | 86.7% | TopicsArrayTreeGraph TheoryTopological Sort |
| 56. Merge Intervals | Medium | 86.7% | TopicsArraySortingQuicksort |
| Remove Invalid Parentheses | Hard | 76.1% | TopicsStringBacktrackingBreadth-First Search |
| 139. Word Break | Medium | 76.1% | TopicsArrayHash TableStringDynamic ProgrammingTrieMemoizationBrute-Force Search |
| 437. Path Sum III | Medium | 76.1% | TopicsTreeDepth-First SearchBinary Tree |
| 98. Validate Binary Search Tree | Medium | 76.1% | TopicsTreeDepth-First SearchBinary Search TreeBinary Tree |
| 49. Group Anagrams | Medium | 76.1% | TopicsArrayHash TableStringSorting |
| 146. LRU Cache | Medium | 76.1% | TopicsHash TableLinked ListDesignDoubly-Linked List |
