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

Question

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 * 104
• s consists of English letters, digits, symbols and spaces.

Python Solution

class Solution:
    def lengthOfLongestSubstring(self, A: str) -> int:
        i = j = result = 0
        sz = len(A)
        storage = set()

        while i < sz and j < sz:
            if A[j] in storage:
                storage.remove(A[i])
                i += 1
            else:
                storage.add(A[j])
                j += 1
                result = max(result, j-i)

        return (result)