Longest Substring Without Repeating Characters

Given a string s, return the length of the longest substring that contains no repeating characters.

---

Example 1

Input: s = "abcabcbb"
Output: 3
Explanation: "abc" is the longest substring with all unique characters.

Example 2

Input: s = "bbbbb"
Output: 1
Explanation: The longest substring with no repeating characters is "b", length 1.

Example 3

Input: s = "pwwkew"
Output: 3
Explanation: "wke" is the longest valid window (length 3); "kew" also works.

---

Constraints

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