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 146 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0169Majority ElementEasy
- 0217Majority Element IIMed
- 0286Bulls and CowsMed
- 0334Top K Frequent ElementsMed
- 0370Ransom NoteEasy
- 0374First Unique Character in a StringEasy
- 0438Sort Characters By FrequencyMed
- 0566Longest Harmonious SubsequenceEasy
- 0577Task SchedulerMed
- 0646Top K Frequent WordsMed
- 0721Reorganize StringMed
- 0765Subdomain Visit CountMed
- 0773Most Common WordEasy
- 0823Reordered Power of 2Med
- 0838Uncommon Words from Two SentencesEasy
- 0854RLE IteratorMed
- 0868X of a Kind in a Deck of CardsEasy
- 08773Sum With MultiplicityMed
- 0899Minimum Increment to Make Array UniqueMed
- 0946Subarrays with K Different IntegersHard
Showing 20 of 146