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 27 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0195Course ScheduleMed
- 0198Course Schedule IIMed
- 0297Minimum Height TreesMed
- 0316Longest Increasing Path in a MatrixHard
- 0756Find Eventual Safe StatesMed
- 0805Loud and RichMed
- 0867Cat and MouseHard
- 1126Sort Items by Groups Respecting DependenciesHard
- 1350Course Schedule IVMed
- 1463Strange Printer IIHard
- 1500Rank Transform of a MatrixHard
- 1584Cat and Mouse IIHard
- 1634Number of Restricted Paths From First to Last NodeMed
- 1696Largest Color Value in a Directed GraphHard
- 1749Count Ways to Build Rooms in an Ant ColonyHard
- 1801Number of Ways to Arrive at DestinationMed
- 1867Parallel Courses IIIHard
- 1926Find All Possible Recipes from Given SuppliesMed
- 1937Maximum Employees to Be Invited to a MeetingHard
- 1997All Ancestors of a Node in a Directed Acyclic GraphMed
Showing 20 of 27