Bug Report for longest-substring-without-duplicates (not enough test cases)

[timamz]

Bug Report for https://neetcode.io/problems/longest-substring-without-duplicates

Please describe the bug below and include any steps to reproduce the bug or screenshots if possible.

I have submitted the solution for the problem "Longest Substring Without Repeating Characters".

class Solution:
    def lengthOfLongestSubstring(self, s: str) -> int:
        if len(s) <= 1: return len(s)

        longest_set = set(s[0])
        cur_longest = 1
        l = 0
        for r in range(1, len(s)):
            if s[r] == s[l]:
                l += 1
            else:
                if s[r] not in longest_set:
                    longest_set.add(s[r])
                    cur_longest = max(cur_longest, len(longest_set))
                else:

                    longest_set = set(s[r])
                    l = r

        return cur_longest

The submission was accepted but the solution is incorrect (checked on leetcode). For example for the input s="ohvhjdml" proposed solution yields 5 while the correct answer is 6.