Your question is Longest Unique Substring in Eno. Start with the requirements on the right.
Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.
In Capital One's Eno chat experience, repeated characters can indicate noisy input. Given a string s, write a function that returns the length of the longest substring that contains no repeated characters.
A substring must be contiguous. Your solution should run efficiently for large inputs.
sdef longest_unique_substring(s):