1Longest Substring Without Repeating CharactersMediumHash TableStringSliding Window
Solve → 2Longest Substring Without Repeating CharactersMediumHash TableStringSliding Window
Solve → 3Find All Anagrams in a StringMediumHash TableStringSliding Window
Solve → 4Find Duplicate SubtreesMediumHash TableTreeDepth-First Search
Solve → 5Longest Substring with At Most K Distinct CharactersMediumHash TableStringSliding Window
Solve → 6Permutation in StringMediumHash TableTwo PointersString
Solve → 7Longest Substring Without Repeating CharactersMediumHash TableStringSliding Window
Solve → 8Isomorphic StringsEasyHash TableString
Solve → 9Permutation in StringMediumHash TableTwo PointersString
Solve → 10Find All Anagrams in a StringMediumHash TableStringSliding Window
Solve → 11Find Duplicate SubtreesMediumHash TableTreeDepth-First Search
Solve → 12LRU CacheMediumHash TableLinked ListDesign
Solve → 13Count Substrings Without Repeating CharacterMediumHash TableStringSliding Window
Solve → 14Longest Substring with At Most K Distinct CharactersMediumHash TableStringSliding Window
Solve → 15Longest Repeating Character ReplacementMediumHash TableStringSliding Window
Solve → 16Minimum Window SubstringHardHash TableStringSliding Window
Solve → 17Letter Combinations of a Phone NumberMediumHash TableStringBacktracking
Solve → 18Valid AnagramEasyHash TableStringSorting
Solve → 19Longest Substring with At Least K Repeating CharactersMediumHash TableStringDivide and Conquer
Solve → 20First Unique Character in a StringEasyHash TableStringQueue
Solve → 21Lowest Common Ancestor of a Binary Tree IIIMediumHash TableTwo PointersTree
Solve → 22Linked List CycleEasyHash TableLinked ListTwo Pointers
Solve → 23Jewels and StonesEasyHash TableString
Solve → 24Longest Substring Without Repeating CharactersMediumHash TableStringSliding Window
Solve → 25Isomorphic StringsEasyHash TableString
Solve → 26Permutation in StringMediumHash TableTwo PointersString
Solve → 27Find All Anagrams in a StringMediumHash TableStringSliding Window
Solve → 28Find Duplicate SubtreesMediumHash TableTreeDepth-First Search
Solve → 29LRU CacheMediumHash TableLinked ListDesign
Solve → 30Longest Substring with At Most K Distinct CharactersMediumHash TableStringSliding Window
Solve → 31Count Substrings Without Repeating CharacterMediumHash TableStringSliding Window
Solve → 32Longest Repeating Character ReplacementMediumHash TableStringSliding Window
Solve → 33Minimum Window SubstringHardHash TableStringSliding Window
Solve → 34Letter Combinations of a Phone NumberMediumHash TableStringBacktracking
Solve → 35Linked List CycleEasyHash TableLinked ListTwo Pointers
Solve → 36Valid AnagramEasyHash TableStringSorting
Solve → 37First Unique Character in a StringEasyHash TableStringQueue
Solve → 38Longest Substring with At Least K Repeating CharactersMediumHash TableStringDivide and Conquer
Solve → 39Jewels and StonesEasyHash TableString
Solve → 40Lowest Common Ancestor of a Binary Tree IIIMediumHash TableTwo PointersTree
Solve → 41Path CrossingEasyHash TableString
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