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 132 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0003Longest Substring Without Repeating CharactersMed
- 0030Substring with Concatenation of All WordsHard
- 0076Minimum Window SubstringHard
- 0177Repeated DNA SequencesMed
- 0197Minimum Size Subarray SumMed
- 0207Contains Duplicate IIEasy
- 0208Contains Duplicate IIIHard
- 0227Sliding Window MaximumHard
- 0382Longest Substring with At Least K Repeating CharactersMed
- 0400Arithmetic SlicesMed
- 0411Longest Repeating Character ReplacementMed
- 0425Find All Anagrams in a StringMed
- 0467Sliding Window MedianHard
- 0550Permutation in StringMed
- 0566Longest Harmonious SubsequenceEasy
- 0586Smallest Range Covering Elements from K ListsHard
- 0597Maximum Average Subarray IEasy
- 0612Find K Closest ElementsMed
- 0643Maximum Sum of 3 Non-Overlapping SubarraysHard
- 0667Subarray Product Less Than KMed
Showing 20 of 132