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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