Longest Substring Without Repeating Characters

Medium · Sliding Window

You are given a string. Find the length of the longest contiguous run of characters in it that contains no repeated character. Return that length as an integer.

Examples

Input:  s = "abcabcbb"
Output: 3
Why:    The longest run with no repeated character is "abc", which has length 3.

Input:  s = "bbbbb"
Output: 1
Why:    Every character is the same, so the best we can do is a single character.

Input:  s = "pwwkew"
Output: 3
Why:    "wke" is the longest stretch without a repeat; "pwke" is not contiguous in the original string so it doesn't count.

Constraints

0 <= s.length <= 5 * 10^4, s consists of English letters, digits, symbols and spaces.

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Practise Longest Substring Without Repeating Characters

This statement is written for CodeSpeek. The problem is part of the NeetCode 150 list; Watch NeetCode's explanation of Longest Substring Without Repeating Characters. Reference solutions from the NeetCode repository (MIT) are used to verify our tests.