Given a string s, return the length of the longest contiguous substring that contains no repeated characters. The input is a single string, and the output is a single integer.
Example 1:
Input: s = "abcabcbb"
Output: 3
Explanation: The longest substring without repeating characters is "abc".
Example 2:
Input: s = "pwwkew"
Output: 3
Explanation: The longest substring without repeating characters is "wke".
0 <= len(s) <= 10^5s consists of ASCII letters, digits, symbols, and spaces