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Longest Substring Without Repeating Characters

Find the length of the longest contiguous substring that contains no repeated characters.

Acceptance 88%
Problem Statement

Longest Substring Without Repeating Characters

Given a string s, find the length of the longest contiguous substring whose characters are all distinct.

A substring must consist of consecutive characters from the original string. You only need to return the maximum length, not the substring itself.

Input Format

  • A single string s.
  • The string may contain lowercase letters, uppercase letters, digits, spaces, or other visible characters depending on the platform variant.

Output Format

  • Return a single integer: the length of the longest substring of s with all unique characters.

Constraints

  • 0 <= s.length
  • The exact upper bound depends on the platform variant.
  • A linear-time solution is expected for interview use.
Examples
Sample cases returned by the problem API.

Example 1

Input

s = "abcabcbb"

Output

3

Explanation

The longest substrings without repeating characters are "abc", "bca", and "cab". Their length is 3.

Example 2

Input

s = "bbbbb"

Output

1

Explanation

Every substring with more than one character repeats b, so the best you can do is a single character.

Show 1 more example

Example 3

Input

s = "pwwkew"

Output

3

Explanation

One longest valid substring is "wke", which has length 3.

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