output_description: Print the minimum number of elements that needs to be replaced.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      n
      v_1 v_2 ... v_n
attempt: if __name__ == '__main__':                                                                                                                                                  n = int(input())
      vs = list(map(int, input().split()))
  
      even = vs[::2]
      odd = vs[1::2]
  
      from collections import Counter
  
      result = 0
      #evenの処理
      ce = Counter(even)
      emode = ce.most_common(1)[0]
  
      oe = Counter(odd)
      omode = oe.most_common(1)[0]
      if emode[0] == omode[0]:
          if emode[1] > omode[1]:
              for i in range(len(even)):
                  if even[i] != emode[0]:
                      result += 1
              if len(oe.most_common()) == 1:
                  omode = -1
                  result += len(odd)
              else:
                  omode = oe.most_common(2)[0][0]
                  for i in range(len(odd)):
                      if odd[i] != omode:
                          result += 1
  
          else:
              for i in range(len(odd)):
                  if odd[i] != omode[0]:
                      result += 1
              if len(ce.most_common()) == 1:
                  emode = -1
                  result += len(even)
              else:
                  emode = ce.most_common(2)[0][0]
                  for i in range(len(even)):
                      if even[i] != emode:
                          result += 1
      else:
          for i in range(len(even)):
              if even[i] != emode[0]:
                  result += 1
          for i in range(len(odd)):
              if odd[i] != omode[0]:
                  result += 1
  
      print(result)
problem_description: Statement
  
  A sequence a_1,a_2,... ,a_n is said to be /\/\/\/ when the following
  conditions are satisfied:
  
    * For each i = 1,2,..., n-2, a_i = a_{i+2}.
    * Exactly two different numbers appear in the sequence.
  
  You are given a sequence v_1,v_2,...,v_n whose length is even. We would like
  to make this sequence /\/\/\/ by replacing some of its elements. Find the
  minimum number of elements that needs to be replaced.
samples: [{"input": "4\n    3 1 3 2", "output": "1\n    \n\nThe sequence 3,1,3,2 is not /\\/\\/\\/, but we can make it /\\/\\/\\/ by replacing\none of its elements: for example, replace the fourth element to make it\n3,1,3,1.\n\n* * *"}, {"input": "6\n    105 119 105 119 105 119", "output": "0\n    \n\nThe sequence 105,119,105,119,105,119 is /\\/\\/\\/.\n\n* * *"}, {"input": "4\n    1 1 1 1", "output": "2\n    \n\nThe elements of the sequence 1,1,1,1 are all the same, so it is not /\\/\\/\\/."}]