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 31 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0005Longest Palindromic SubstringMed
- 0029Divide Two IntegersMed
- 0031Next PermutationMed
- 0033Search in Rotated Sorted ArrayMed
- 0042Trapping Rain WaterHard
- 0045Jump Game IIMed
- 0056Merge IntervalsMed
- 0063Unique Paths IIMed
- 0079Word SearchMed
- 0084Largest Rectangle in HistogramHard
- 0128Longest Consecutive SequenceMed
- 0134Gas StationMed
- 0146LRU CacheMed
- 0162Find Peak ElementMed
- 0188Number of IslandsMed
- 0227Sliding Window MaximumHard
- 0411Longest Repeating Character ReplacementMed
- 0424Path Sum IIIMed
- 0641Longest Univalue PathMed
- 0706Open the LockMed
Showing 20 of 31