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Longest Substring Without Repeats
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Longest Substring Without Repeats

MediumPython

Problem

Write an algorithm to find the longest substring without repeating characters.

Implement the function below. Given a string s, return the length of its longest contiguous substring in which every character appears at most once. Return 0 for an empty string. The solution should run in linear time.

Function: length_of_longest_substring(s)

Example: s = "abcabcbb" returns 3, because "abc" is the longest valid substring.

Constraints

  • 0 <= len(s) <= 50000
  • s contains printable ASCII characters
  • The result is the length of a contiguous substring

Function Signature

def length_of_longest_substring(s):
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