Longest Unique Substring

Given a string s, your task is to find the length of the longest substring that contains no duplicate characters.

You are required to implement an algorithm to compute the maximum length of a substring with all unique characters. Mathematically, if we denote a substring by s[i..j], find the maximum value of j - i + 1 such that every character in s[i..j] is unique. This can be expressed as:

\( \max_{0 \leq i \leq j < n} \{ j - i + 1 \mid \text{all characters in } s[i..j]\text{ are distinct} \} \)

The problem tests your understanding of sliding window techniques and hash table usage.

inputFormat

The input consists of a single string s provided via standard input (stdin). The string may contain letters, digits, and/or symbols and can be empty.

outputFormat

Output a single integer representing the length of the longest substring without repeating characters to standard output (stdout).

abcabcbb

3