DSA
Master the patterns
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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
17 of 17 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0001Two SumEasy
- 0013Roman to IntegerEasy
- 0023Merge k Sorted ListsHard
- 0076Minimum Window SubstringHard
- 0146LRU CacheMed
- 0188Number of IslandsMed
- 0334Top K Frequent ElementsMed
- 0367Insert Delete GetRandom O(1)Med
- 0417Flatten a Multilevel Doubly Linked ListMed
- 0601Palindromic SubstringsMed
- 0651Degree of an ArrayEasy
- 0667Subarray Product Less Than KMed
- 0689Asteroid CollisionMed
- 0799Longest Mountain in ArrayMed
- 1251Minimum Number of Steps to Make Two Strings AnagramMed
- 1666Find the Winner of the Circular GameMed
- 2256Maximum Number of Non-overlapping Palindrome SubstringsHard
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