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: # -*- coding: utf-8 -*-
  """
  Created on Fri May 10 23:15:55 2019
  
  @author: Yamazaki Kenichi
  """
  
  n = int(input())
  A = list(map(int, input().split()))
  
  T = [[0 for i in range(10**5 + 1)], [0 for i in range(10**5 + 1)]]
  counta = 0
  for c in A:
      T[counta % 2][c] += 1
      counta += 1
  
  tmp = [[0] * 4, [0] * 4]
  for i in range(10**5 + 1):
      # for i in range(6):
      for k in range(2):
          if T[k][i] > tmp[k][0]:
              tmp[k][2], tmp[k][3] = tmp[k][0], tmp[k][1]
              tmp[k][0], tmp[k][1] = T[k][i], i
          elif T[k][i] > tmp[k][2]:
              tmp[k][2], tmp[k][3] = T[k][i], i
  #        print(tmp)
  if tmp[0][1] != tmp[1][1]:
      print(n - tmp[0][0] - tmp[1][0])
  else:
      print(min(n - tmp[0][0] - tmp[1][2], n - tmp[0][2] - tmp[1][0]))
  
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 /\\/\\/\\/."}]