output_description: If A + B is 10 or greater, print the string `error` (case-sensitive);
  otherwise, print the value of A + B.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      A B
attempt: s = input()
  h = []
  res = True
  for c in s:
      if c in h:
          res = False
          break
      else:
          h.append(c)
  print("yes" if res else "no")
  
problem_description: Statement
  
  You are given two integers A and B as the input. Output the value of A + B.
  
  However, if A + B is 10 or greater, output `error` instead.
samples: [{"input": "6 3", "output": "9\n    \n\n* * *"}, {"input": "6 4", "output": "error"}]