output_description: Among A, B and C, print the integer that is different from the rest.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      A B C
attempt: import sys
  
  
  def main():
  
      # Get Args
      args = _input_args()  # get arguments as an array from console/script parameters.
  
      # Call main Logic
      result = _main(args)
  
      # Output a result in a correct way.
      _output_result(result)
  
  
  def _main(args):
      """Write Main Logic here for the contest.
  
      :param args: arguments
      :type args: list
      :return: result
      :rtype: depends on your logic.
      """
      hash = HashMap()
  
      for value in args:
          hash.add(value)
  
      # Return something.
      return hash.find_unique()
  
  
  class HashMap(object):
      def __init__(self):
          self.map = {}
  
      def add(self, value):
          if self.map.get(value) is None:
              self.map[value] = [value]
          else:
              self.map[value].append(value)
  
      def find_unique(self):
          for value, array in self.map.items():
              if len(array) == 1:
                  return array[0]
  
  
  def _input_args():
  
      arguments = (
          _input().split()
      )  # ptn2: get args from 1 line console prompt with space separated.
  
      return arguments  # This will be array.
  
  
  def _input():
      # If Subject requires interactive input, use this and patch mock in unittest.
      return input()  # Change if necessary.
  
  
  def _output_result(result):
  
      print("{}".format(str(result)))  # Same as above, but more versatile.
  
  
  if __name__ == "__main__":
      main()
  
problem_description: Statement
  
  You are given three integers, A, B and C.  
  Among them, two are the same, but the remaining one is different from the
  rest.  
  For example, when A=5,B=7,C=5, A and C are the same, but B is different.  
  Find the one that is different from the rest among the given three integers.
samples: [{"input": "5 7 5", "output": "7\n    \n\nThis is the same case as the one in the statement.\n\n* * *"}, {"input": "1 1 7", "output": "7\n    \n\nIn this case, C is the one we seek.\n\n* * *"}, {"input": "-100 100 100", "output": "-100"}]