LeetCode: 3. Longest Substring Without Repeating Characters

Problem: 3. Longest Substring Without Repeating Characters

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

Difficulty: Medium

Description:

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

Example 1:

Input: “abcabcbb”
Output: 3
Explanation: The answer is “abc”, with the length of 3.

Example 2:

Input: “bbbbb”
Output: 1
Explanation: The answer is “b”, with the length of 1.

Example 3:

Input: “pwwkew“
Output: 3
Explanation: The answer is “wke”, with the length of 3.
Note that the answer must be a substring, “pwke” is a subsequence and not a substring.

Solution: 

Language: Swift

Runtime: 28ms
Memory: 4.3MB