Question

Write a function repfree(s) that takes as input a string s and checks whether any character appears more than once. The function should return True if there are no repetitions and False otherwise.

Answer 1

Answer:

def repfree(s):

     a=set(s)

     if len(a)==len(s):

            return True

     else:

            return False

Explanation:

set() method is used to convert any of the iterable to the distinct element and sorted sequence of iterable elements, commonly called Set.

Example :   List = [ 3, 4, 1, 4, 5 ]

                   The list before conversion is : [3, 4, 1, 4, 5]

                   The list after conversion is : {1, 3, 4, 5}

Answer 2

The function that takes as input a string s and checks whether any character appears more than once and return True if there are no repetitions and False otherwise is :

import collections

def repetitions(s):

   final_result = collections.Counter(s)

   for i in final_result:

       if final_result[i] > 1:

           return False

   return True