output_description: Print the correct choice.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      A
      B
attempt: print(6 - int(input) - int(input))
  
problem_description: Statement
  
  Takahashi is solving quizzes. He has easily solved all but the last one.
  
  The last quiz has three choices: 1, 2, and 3.
  
  With his supernatural power, Takahashi has found out that the choices A and B
  are both wrong.
  
  Print the correct choice for this problem.
samples: [{"input": "3\n    1", "output": "2\n    \n\nWhen we know 3 and 1 are both wrong, the correct choice is 2.\n\n* * *"}, {"input": "1\n    2", "output": "3"}]