'''simple docstring'''

from __future__ import annotations

import math
def       __UpperCamelCase	(       UpperCAmelCase					):


 if num <= 0:
  lowercase__    :   Union[str, Any]						= F"""{num}: Invalid input, please enter a positive integer."""
  raise ValueError(__UpperCamelCase					)

 lowercase__    :   Dict						= [True] * (num + 1)
 lowercase__    :   Union[str, Any]						= []
 lowercase__    :   str						= 2
 lowercase__    :   List[Any]						= int(math.sqrt(__UpperCamelCase					)					)

 while start <= end:
  # If start is a prime
  if sieve[start] is True:
   prime.append(__UpperCamelCase					)

   # Set multiples of start be False
   for i in range(start * start		,					num + 1		,					__UpperCamelCase					):
    if sieve[i] is True:
     lowercase__    :   Any						= False

  start += 1

 for j in range(end + 1		,					num + 1					):
  if sieve[j] is True:
   prime.append(__UpperCamelCase					)

 return prime


if __name__ == "__main__":
  print(prime_sieve(int(input("""Enter a positive integer: """).strip())))





'''simple docstring'''

def       __UpperCamelCase	(       UpperCAmelCase					):
 if not all(x.isalpha() for x in string					):
  raise ValueError('''String must only contain alphabetic characters.'''					)

 lowercase__    :   Tuple						= sorted(string.lower()					)
 return len(UpperCAmelCase					) == len(set(UpperCAmelCase					)					)


if __name__ == "__main__":
  __a:			Union[str, Any]	       =       input("""Enter a string """).strip()

  __a:			Tuple	       =       is_isogram(input_str)
  print(F'{input_str} is {"an" if isogram else "not an"} isogram.')

