Longest Substring Without Repeating

Difficulty: Medium · Topic: Arrays & strings

Given a string s, return the length of the longest substring without repeating characters. Slide a window; when a character repeats inside it, jump the window start past the previous occurrence.

Examples

length_of_longest_substring("abcabcbb")
→ 3

'abc' has length 3.

length_of_longest_substring("bbbbb")
→ 1

length_of_longest_substring("pwwkew")
→ 3

'wke' — note 'pwke' is not a substring.

Target complexity: time O(n), space O(min(n, alphabet))

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