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 33 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0206The Skyline ProblemHard
- 0294Range Sum Query - MutableMed
- 0302Count of Smaller Numbers After SelfHard
- 0314Count of Range SumHard
- 0393Queue Reconstruction by HeightMed
- 0480Reverse PairsHard
- 0627Number of Longest Increasing SubsequenceMed
- 1088Online Majority Element In SubarrayHard
- 1292Count Number of TeamsMed
- 1304Queries on a Permutation With KeyMed
- 1388Minimum Possible Integer After at Most K Adjacent Swaps On DigitsHard
- 1514Create Sorted Array through InstructionsHard
- 1791Find the Longest Valid Obstacle Course at Each PositionHard
- 1984Count Good Triplets in an ArrayHard
- 1998Minimum Number of Moves to Make PalindromeHard
- 2050Count Number of Rectangles Containing Each PointMed
- 2084Booking Concert Tickets in GroupsHard
- 2191Longest Increasing Subsequence IIHard
- 2208Longest Uploaded PrefixMed
- 2210Number of Pairs Satisfying InequalityHard
Showing 20 of 33