[Leetcode] 0003. Longest Substring Without Repeating Characters

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Table of contents

Medium

Given a string s, find the length of the longest substring without repeating characters.

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.

Constraints:

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

Python

				
					# time complexity: O(n) # space complexity: O(min(m,n)) from collections import Counter class Solution: def lengthOfLongestSubstring(self, s: str) -> int: chars = Counter() left = right = 0 res = 0 while right < len(s): r = s[right] chars[r] += 1 while chars[r] > 1: l = s[left] chars[l] -= 1 left += 1 res = max(res, right - left + 1) right += 1 return res Input = "abcabcbb" print(Solution().lengthOfLongestSubstring(Input))

Medium

Python

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