118. Longest Substring Without Repeating Characters

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Example 1:

Input: s = "abcabcbb"

Output: 3

Explanation: The longest substring without repeating characters is "abc", with length 3.

Example 2:

Input: s = "bbbbb"

Output: 1

Explanation: The longest substring without repeating characters is "b", with length 1.

Example 3:

Input: s = "pwwkew"

Output: 3

Explanation: The longest substring without repeating characters is "wke", with length 3. Note that the answer must be a substring, "pwke" is a subsequence and not a substring.

Example 4:

Input: s = ""

Output: 0

Explanation: An empty string has no substrings, so the length is 0.

Example 5:

Input: s = "dvdf"

Output: 3

Explanation: The longest substring without repeating characters is "vdf", with length 3.

Constraints:

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Time Complexity

O(n)

Space Complexity

O(min(m,n))

118. Longest Substring Without Repeating Characters

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