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 1394 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0002Add Two NumbersMed
- 0003Longest Substring Without Repeating CharactersMed
- 0005Longest Palindromic SubstringMed
- 0006Zigzag ConversionMed
- 0007Reverse IntegerMed
- 0008String to Integer (atoi)Med
- 0011Container With Most WaterMed
- 0012Integer to RomanMed
- 00153SumMed
- 00163Sum ClosestMed
- 0017Letter Combinations of a Phone NumberMed
- 00184SumMed
- 0019Remove Nth Node From End of ListMed
- 0022Generate ParenthesesMed
- 0024Swap Nodes in PairsMed
- 0029Divide Two IntegersMed
- 0031Next PermutationMed
- 0033Search in Rotated Sorted ArrayMed
- 0034Find First and Last Position of Element in Sorted ArrayMed
- 0036Valid SudokuMed
Showing 20 of 1394