Longest Substring Without Repeating Characters

4. Longest Substring Without Repeating Characters

Output: 3

class Solution():
    def noRepeat(self, str):
        longest, l = 0, 0
        curr = {}

        for letter in str:
            while letter in curr:
                longest = max(longest, len(curr))
                curr[str[l]] -= 1

                if curr[str[l]] == 0:
                    del curr[str[l]]

                l += 1
            
            if letter not in curr:
                curr[letter] = 1
            else:
                curr[letter] += 1
            
            longest = max(longest, len(curr))
        
        return longest
            
str = "abccde"

p1 = Solution()
print(p1.noRepeat(str))