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 133 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0133Clone GraphMed
- 0195Course ScheduleMed
- 0198Course Schedule IIMed
- 0297Minimum Height TreesMed
- 0316Longest Increasing Path in a MatrixHard
- 0319Reconstruct ItineraryHard
- 0386Evaluate DivisionMed
- 0531Number of ProvincesMed
- 0638Redundant ConnectionMed
- 0639Redundant Connection IIHard
- 0697Network Delay TimeMed
- 0707Cracking the SafeHard
- 0719Couples Holding HandsHard
- 0739Is Graph Bipartite?Med
- 0741Cheapest Flights Within K StopsMed
- 0751All Paths From Source to TargetMed
- 0756Find Eventual Safe StatesMed
- 0788Sum of Distances in TreeHard
- 0795Keys and RoomsMed
- 0801Shortest Path Visiting All NodesHard
Showing 20 of 133