DSA
Master the patterns
Search the bank, then filter by difficulty, pattern, data structure, or algorithm. Each problem includes approaches, solutions, and walkthroughs.
Active·2,723
Easy·667
Medium·1,394
Hard·662
Patterns
Recognize the move
Filter the bank by pattern — each card links into the problem index.
Problem index
Browse problems
Search by title, then refine with facets. Sorted by problem ID.
Difficulty
Facets
12 of 12 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0023Merge k Sorted ListsHard
- 0033Search in Rotated Sorted ArrayMed
- 0036Valid SudokuMed
- 0057Insert IntervalMed
- 0068Text JustificationHard
- 0139Word BreakMed
- 0146LRU CacheMed
- 0224Lowest Common Ancestor of a Binary TreeMed
- 0227Sliding Window MaximumHard
- 0336Intersection of Two ArraysEasy
- 0576Merge Two Binary TreesEasy
- 1852Stock Price Fluctuation Med
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