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 28 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0025Reverse Nodes in k-GroupHard
- 0115Distinct SubsequencesHard
- 0397Split Array Largest SumHard
- 0411Longest Repeating Character ReplacementMed
- 0487Keyboard RowEasy
- 0511Beautiful ArrangementMed
- 0549Reshape the MatrixEasy
- 0592Shopping OffersMed
- 0788Sum of Distances in TreeHard
- 0922Binary Tree CamerasHard
- 1001Longest String ChainMed
- 1066Minimum Cost Tree From Leaf ValuesMed
- 1092Last Substring in Lexicographical OrderHard
- 1202Convert Binary Number in a Linked List to IntegerEasy
- 1234Break a PalindromeMed
- 1513Sell Diminishing-Valued Colored BallsMed
- 1836Maximum Difference Between Increasing ElementsEasy
- 1856Remove Colored Pieces if Both Neighbors are the Same ColorMed
- 2228Count Subarrays With Fixed BoundsHard
- 2246Total Cost to Hire K WorkersMed
Showing 20 of 28