output_description: If all the characters in S are different, print `yes` (case-sensitive);
  otherwise, print `no`.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      S
attempt: def ri():
      return int(input())
  
  
  def rli():
      return list(map(int, input().split()))
  
  
  def rls():
      return list(input())
  
  
  def pli(a):
      return "".join(list(map(str, a)))
  
  
  S = rls()
  print("yes" if len(S) == len(set(S)) else "no")
  
problem_description: Statement
  
  You are given a string S consisting of lowercase English letters. Determine
  whether all the characters in S are different.
samples: [{"input": "uncopyrightable", "output": "yes\n    \n\n* * *"}, {"input": "different", "output": "no\n    \n\n* * *"}, {"input": "no", "output": "yes"}]