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 39 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0213Implement Stack using QueuesEasy
- 0220Implement Queue using StacksEasy
- 0227Sliding Window MaximumHard
- 0328Flatten Nested List IteratorMed
- 0374First Unique Character in a StringEasy
- 0578Design Circular QueueMed
- 0595Design Circular DequeMed
- 0603Dota2 SenateMed
- 0816Shortest Subarray with Sum at Least KHard
- 0872Maximum Sum Circular SubarrayMed
- 0887Number of Recent CallsEasy
- 0890Stamping The SequenceHard
- 0904Reveal Cards In Increasing OrderMed
- 0949Minimum Number of K Consecutive Bit FlipsHard
- 1318Constrained Subsequence SumHard
- 1330Longest Continuous Subarray With Absolute Diff Less Than or Equal to LimitMed
- 1383Max Value of EquationHard
- 1532Design Front Middle Back QueueMed
- 1547Delivering Boxes from Storage to PortsHard
- 1555Jump Game VIMed
Showing 20 of 39