Longest Distinct characters in string Python

PROGRAM TO FIND THE LENGTH OF THE LONGEST SUBSTRING WITHOUT REPEATING CHARACTERS

def longestUniqueSubsttr(string):

       

    # Creating a set to store the last positions of occurrence

    seen = {}

    maximum_length = 0

   

    # starting the inital point of window to index 0

    start = 0 

       

    for end in range(len(string)):

   

        # Checking if we have already seen the element or not

        if string[end] in seen:

  

            # If we have seen the number, move the start pointer

            # to position after the last occurrence

            start = max(start, seen[string[end]] + 1)

   

        # Updating the last seen value of the character

        seen[string[end]] = end

        maximum_length = max(maximum_length, end-start + 1)

    return maximum_length

   

# Driver Code

string = "geeksforgeeks"

print("The input string is", string)

length = longestUniqueSubsttr(string)

print("The length of the longest non-repeating character substring is", length)




OUTPUT

The input string is geeksforgeeks
The length of the longest non-repeating character substring is 7

CREDITS: https://www.geeksforgeeks.org/length-of-the-longest-substring-without-repeating-characters/