DSA
Master the patterns
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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
18 of 18 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0001Two SumEasy
- 00153SumMed
- 0020Valid ParenthesesEasy
- 0046PermutationsMed
- 0053Maximum SubarrayMed
- 0070Climbing StairsEasy
- 0088Merge Sorted ArrayEasy
- 0188Number of IslandsMed
- 0193Isomorphic StringsEasy
- 0222Palindrome Linked ListEasy
- 0373Lexicographical NumbersMed
- 0825Minimum Number of Refueling StopsHard
- 1937Maximum Employees to Be Invited to a MeetingHard
- 2533Furthest Point From OriginEasy
- 2641Double Modular ExponentiationMed
- 2726Count Submatrices with Top-Left Element and Sum Less Than kMed
- 2736Mark Elements on Array by Performing QueriesMed
- 3089Lexicographically Smallest Generated StringHard
All 18 matching problems loaded