3. Longest Substring Without Repeating Characters

https://leetcode.com/problems/longest-substring-without-repeating-characters

Python

Test Cases

"abcabcbb"
" "
"ok"
"dvdf"

class Solution:
    def lengthOfLongestSubstring(self, s: str) -> int:
        if len(s) < 2:
            return len(s)

        chars = set()
        max_length, left, right = 0, 0, 0
        while right < len(s):
            if s[right] not in chars:
                chars.add(s[right])
                max_length = max(max_length, len(chars))
                right += 1
                continue
            chars.remove(s[left])
            left += 1

        return max_length

Python​

Python