Problem

In Capital One's Eno chat experience, repeated characters can indicate noisy input. Given a string s, write a function that returns the length of the longest substring that contains no repeated characters.

A substring must be contiguous. Your solution should run efficiently for large inputs.

Input and Output

• Input: A string s
• Output: An integer representing the maximum length of a substring with all unique characters

Examples

Example 1

Input: s = "abcabcbb"
Output: 3

Explanation: The longest substring without repeating characters is "abc", which has length 3.

Example 2

Input: s = "bbbbb"
Output: 1

Explanation: Every substring longer than length 1 repeats the character b, so the answer is 1.

Example 3

Input: s = "pwwkew"
Output: 3

Explanation: One valid longest substring is "wke". "pwke" is not valid because it is not contiguous.

Constraints

• 0 <= len(s) <= 10^5
• s contains printable ASCII characters
• Return the length only, not the substring itself