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
20 of 26 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0022Generate ParenthesesMed
- 0033Search in Rotated Sorted ArrayMed
- 0042Trapping Rain WaterHard
- 0056Merge IntervalsMed
- 0062Unique PathsMed
- 0069Sqrt(x)Easy
- 0070Climbing StairsEasy
- 0079Word SearchMed
- 0133Clone GraphMed
- 0139Word BreakMed
- 0140Word Break IIHard
- 0150Evaluate Reverse Polish NotationMed
- 0177Repeated DNA SequencesMed
- 0188Number of IslandsMed
- 0196Implement Trie (Prefix Tree)Med
- 0367Insert Delete GetRandom O(1)Med
- 0391Sum of Left LeavesEasy
- 0494Perfect NumberEasy
- 0599Set MismatchEasy
- 0715Special Binary StringHard
Showing 20 of 26