Python challenge: Leetcode 3. Longest Substring Without Repeating Characters

>Find the length of the longest substring without repeating characters. initialise the length_of_s equals to length of s initialise the length_list_of_sub_string to the empty string define a find_and_record_substring program: initialise seen_string as an empty string initialise seen_dictionary as an empty dictionary initialise the length equals to 0 for each character in s: if the charcter do not found in seen_string: add the character to seen_string otherwise: initialise the length equals to length of seen_string update seen_dictionary with length as key, seen_string as value set seen_string to empty string add the character to seen_string return the maximum of the key of the dictionary >>find and record each substring without repeating characters in the string s repeat the find_and_record_substring program for the length of s times: add the result of find_and_record_substring program to length_list_of_sub_string set s to a s that remove the first character >>return the longest substring without repeating characters return longest length equals to the maximum of length_list_of_sub_string 

class Solution: def lengthOfLongestSubstring(self, s: str) -> int: length_of_s = len(s) length_list_of_sub_string = [] # program to find each substring without repeating characters in the string  def find_and_record_substring(str1: str): seen_string = "" seen_dict = {} for char in str1: if char not in seen_string: seen_string += char # if char found in seen_string  else: # add the current seen_string to dict first  length_of_seen_string = len(seen_string) seen_dict.update({length_of_seen_string: seen_string}) # clear the seen_string and continue to build seen_string  seen_string = "" seen_string += char # should add the current seen_string to dict  length_of_seen_string = len(seen_string) seen_dict.update({length_of_seen_string: seen_string}) longest_length = max(seen_dict.keys()) return longest_length if s == "": return 0 while length_of_s != 0: length_list_of_sub_string.append(find_and_record_substring(s)) # remove the first charcter of s  s = s[1::] # update the length of s  length_of_s = len(s) return max(length_list_of_sub_string) 

class Solution: def lengthOfLongestSubstring(self, s: str) -> int: length_of_s = len(s) length_list_of_sub_string = [] temp_max = 0 def longest(str1): set1 = set(str1) return len(set1) max_limit = longest(s) def find_and_record_substring(str1: str): seen_string = "" seen_dict = {} for char in str1: if char not in seen_string: seen_string += char else: length_of_seen_string = len(seen_string) seen_dict.update({length_of_seen_string: seen_string}) seen_string = "" seen_string += char length_of_seen_string = len(seen_string) seen_dict.update({length_of_seen_string: seen_string}) longest_length = max(seen_dict.keys()) return longest_length if s == "": return 0 while length_of_s != 0 and temp_max < length_of_s and temp_max < max_limit: length_list_of_sub_string.append(find_and_record_substring(s)) s = s[1::] length_of_s = len(s) temp_max = max(length_list_of_sub_string) return max(length_list_of_sub_string) 

def lengthOfLongestSubstring(s: str) -> int: # Base condition  if s == "": return 0 # Starting index of window  start = 0 # Ending index of window  end = 0 # Maximum length of substring without repeating characters  maxLength = 0 # Set to store unique characters  unique_characters = set() # Loop for each character in the string  while end < len(s): if s[end] not in unique_characters: unique_characters.add(s[end]) end += 1 maxLength = max(maxLength, len(unique_characters)) else: unique_characters.remove(s[start]) start += 1 return maxLength