Longest Substring Without Repeating Characters

Medium

Sliding Window

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 "pwke" is a subsequence and not a substring.

Constraints

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

Show Hints (3)

Hint 1: Use a sliding window with two pointers.

Hint 2: Use a Set or Map to track characters in the current window.

Hint 3: When you find a duplicate, shrink the window from the left until the duplicate is removed.

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Test Results

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