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
14 of 14 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0023Merge k Sorted ListsHard
- 0146LRU CacheMed
- 0181Number of 1 BitsEasy
- 0215Basic Calculator IIMed
- 0422Non-overlapping IntervalsMed
- 0527Diameter of Binary TreeEasy
- 0615Image SmootherEasy
- 0797Guess the WordHard
- 0821Transpose MatrixEasy
- 0935Time Based Key-Value StoreMed
- 0940Interval List IntersectionsMed
- 1079Snapshot ArrayMed
- 1151Remove Sub-Folders from the FilesystemMed
- 1153Maximum Profit in Job SchedulingHard
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