# LeetCode — Longest Substring without reapting characters (MSFT)

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.

Solution:

Time complexity: O(N)

Space complexity: O(N)