Longest Substring Without Repeating Characters (C#) | Interview Prep

// Longest Substring Without Repeating Characters — MEDIUM

// Category: string

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

Hint: Use a sliding window — keep a set of current characters, expand the right pointer, and shrink the left pointer when a duplicate is found.

Example: s = "abcabcbb"

Output: 3

Longest Substring Without Repeating Characters — Pro only