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Longest Substring Without Repeating Characters

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Given a string s, find the length of the longest substring without repeating characters.

A substring is a contiguous non-empty sequence of characters within a string.

Examples

Example 1

Input: s = "abcabcbb"
Output: 3

The answer is "abc", with the length of 3.

Example 2

Input: s = "bbbbb"
Output: 1

The answer is "b", with the length of 1.

Example 3

Input: s = "pwwkew"
Output: 3

The answer is "wke", with the length of 3. Note that the answer must be a substring, "pwke" is a subsequence and not a substring.

Constraints

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

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