MediumStrings
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.
Example 1:
Input: s = "abcabcbb"
Output: 3
Explanation: The answer is "abc", with the length of 3.
Example 2:
Input: s = "bbbbb"
Output: 1
Explanation: The answer is "b", with the length of 1.
Example 3:
Input: s = "pwwkew"
Output: 3
Explanation: The answer is "wke", with the length of 3. Notice that the answer must be a substring, "pwke" is a subsequence and not a substring.
Examples
Example 1
Input: s = "abcabcbb"
Output: 3
Explanation: The longest substring without repeating characters is "abc" (indices 0-2), length 3.
Example 2
Input: s = "pwwkew"
Output: 3
Explanation: The longest substring without repeating characters is "wke" (indices 2-4) or "kew" (indices 3-5), length 3.
Constraints
- -0 <= s.length <= 5 * 10^4
- -s consists of English letters, digits, symbols and spaces.
Optimal Complexity
Time
O(n)
Space
O(min(n, m))
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