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 96 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0004Median of Two Sorted ArraysHard
- 0017Letter Combinations of a Phone NumberMed
- 00184SumMed
- 0020Valid ParenthesesEasy
- 0022Generate ParenthesesMed
- 0025Reverse Nodes in k-GroupHard
- 0031Next PermutationMed
- 0032Longest Valid ParenthesesHard
- 0034Find First and Last Position of Element in Sorted ArrayMed
- 0039Combination SumMed
- 0042Trapping Rain WaterHard
- 0045Jump Game IIMed
- 0048Rotate ImageMed
- 0053Maximum SubarrayMed
- 0054Spiral MatrixMed
- 0056Merge IntervalsMed
- 0062Unique PathsMed
- 0072Edit DistanceMed
- 0075Sort ColorsMed
- 0084Largest Rectangle in HistogramHard
Showing 20 of 96