Your question is Longest Substring Without Repeats. 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.
Solve a problem where you need to find the longest substring without repeating characters.
Implement def length_of_longest_substring(s):, which accepts a string and returns the length of its longest contiguous substring containing no repeated characters. Aim for an O(n) solution using a sliding window.
def length_of_longest_substring(s):