Practice
The DSA Platform
Technical interview practice problems.
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670 problems
670 problems · showing 1-100
1/7- 01Two SumEasy
- 02Add Two NumbersMedium
- 03Longest Substring Without Repeating CharactersMedium
- 04Median of Two Sorted ArraysHard
- 05Longest Palindromic SubstringMedium
- 06Zigzag ConversionMedium
- 07Reverse IntegerMedium
- 08String to Integer (atoi)Medium
- 09Palindrome NumberEasy
- 10Regular Expression MatchingHard
- 11Container With Most WaterMedium
- 12Integer to RomanMedium
- 13Roman to IntegerEasy
- 14Longest Common PrefixEasy
- 153SumMedium
- 163Sum ClosestMedium
- 17Letter Combinations of a Phone NumberMedium
- 184SumMedium
- 19Remove Nth Node From End of ListMedium
- 20Valid ParenthesesEasy
- 21Merge Two Sorted ListsEasy
- 22Generate ParenthesesMedium
- 23Merge k Sorted ListsHard
- 24Swap Nodes in PairsMedium
- 25Reverse Nodes in k-GroupHard
- 26Remove Duplicates from Sorted ArrayEasy
- 27Remove ElementEasy
- 28Find the Index of the First Occurrence in a StringEasy
- 29Divide Two IntegersMedium
- 30Substring with Concatenation of All WordsHard
- 31Next PermutationMedium
- 32Longest Valid ParenthesesHard
- 33Search in Rotated Sorted ArrayMedium
- 34Find First and Last Position of Element in Sorted ArrayMedium
- 35Search Insert PositionEasy
- 36Valid SudokuMedium
- 37Sudoku SolverHard
- 38Count and SayMedium
- 39Combination SumMedium
- 40Combination Sum IIMedium
- 41First Missing PositiveHard
- 42Trapping Rain WaterHard
- 43Multiply StringsMedium
- 44Wildcard MatchingHard
- 45Jump Game IIMedium
- 46PermutationsMedium
- 47Permutations IIMedium
- 48Rotate ImageMedium
- 49Group AnagramsMedium
- 50Pow(x, n)Medium
- 51N-QueensHard
- 52N-Queens IIHard
- 53Maximum SubarrayMedium
- 54Spiral MatrixMedium
- 55Jump GameMedium
- 56Merge IntervalsMedium
- 57Insert IntervalMedium
- 58Length of Last WordEasy
- 59Spiral Matrix IIMedium
- 60Permutation SequenceHard
- 61Rotate ListMedium
- 62Unique PathsMedium
- 63Unique Paths IIMedium
- 64Minimum Path SumMedium
- 65Valid NumberHard
- 66Plus OneEasy
- 67Add BinaryEasy
- 68Text JustificationHard
- 69Sqrt(x)Easy
- 70Climbing StairsEasy
- 71Simplify PathMedium
- 72Edit DistanceMedium
- 73Set Matrix ZeroesMedium
- 74Search a 2D MatrixMedium
- 75Sort ColorsMedium
- 76Minimum Window SubstringHard
- 77CombinationsMedium
- 78SubsetsMedium
- 79Word SearchMedium
- 80Remove Duplicates from Sorted Array IIMedium
- 81Search in Rotated Sorted Array IIMedium
- 82Remove Duplicates from Sorted List IIMedium
- 83Remove Duplicates from Sorted ListEasy
- 84Largest Rectangle in HistogramHard
- 85Maximal RectangleHard
- 86Partition ListMedium
- 87Scramble StringHard
- 88Merge Sorted ArrayEasy
- 89Gray CodeMedium
- 90Subsets IIMedium
- 91Decode WaysMedium
- 92Reverse Linked List IIMedium
- 93Restore IP AddressesMedium
- 94Binary Tree Inorder TraversalEasy
- 95Unique Binary Search Trees IIMedium
- 96Unique Binary Search TreesMedium
- 97Interleaving StringMedium
- 98Validate Binary Search TreeMedium
- 99Recover Binary Search TreeMedium
- 100Same TreeEasy