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 88 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0004Median of Two Sorted ArraysHard
- 0010Regular Expression MatchingHard
- 0011Container With Most WaterMed
- 0012Integer to RomanMed
- 00153SumMed
- 0017Letter Combinations of a Phone NumberMed
- 0023Merge k Sorted ListsHard
- 0037Sudoku SolverHard
- 0039Combination SumMed
- 0042Trapping Rain WaterHard
- 0046PermutationsMed
- 0047Permutations IIMed
- 0049Group AnagramsMed
- 0050Pow(x, n)Med
- 0051N-QueensHard
- 0056Merge IntervalsMed
- 0069Sqrt(x)Easy
- 0070Climbing StairsEasy
- 0071Simplify PathMed
- 0079Word SearchMed
Showing 20 of 88