Problem:
Score : 300 points

Problem 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.

Constraints

2 \leq n \leq 10^5

n is even.

1 \leq v_i \leq 10^5

v_i is an integer.

Input

Input is given from Standard Input in the following format:

n
v_1 v_2 ... v_n

Output

Print the minimum number of elements that needs to be replaced.

Sample Input 1

4
3 1 3 2

Sample Output 1

1

The sequence 3,1,3,2 is not /\/\/\/, but we can make it /\/\/\/ by replacing one of its elements: for example, replace the fourth element to make it 3,1,3,1.

Sample Input 2

6
105 119 105 119 105 119

Sample Output 2

0

The sequence 105,119,105,119,105,119 is /\/\/\/.

Sample Input 3

4
1 1 1 1

Sample Output 3

2

The elements of the sequence 1,1,1,1 are all the same, so it is not /\/\/\/.

Solution in Python (3.4.3) (judge verdict: Wrong Answer)

import collections
N = int(input())
V = input().split(' ')

EVEN = V[0::2]
ODD = V[1::2]
EVEN_V = collections.Counter(EVEN)
ODD_V = collections.Counter(ODD)

A = len(EVEN_V)
B = len(ODD_V)


if EVEN_V.most_common()[0][1] >= ODD_V.most_common()[0][1]:
  MAX_ELE = EVEN_V.most_common()[0][0]
  count_max =EVEN_V.most_common()[0][1]
  for i in range(B):
    if MAX_ELE != ODD_V.most_common()[0][0]:
      SECOND_ELE = ODD_V.most_common()[i][0]
      count_SEC = ODD_V.most_common()[i][1]
      break
    else:
      count_SEC = B
  
else:
  MAX_ELE = ODD_V.most_common()[0][0]
  count_max = ODD_V.most_common()[0][1]
  for i in range(A):
    if MAX_ELE != EVEN_V.most_common()[i][0]:
      SECOND_ELE =EVEN_V.most_common()[i][0]
      count_SEC = EVEN_V.most_common()[i][1]
      break
    else:
      count_SEC = A
print((N- int(count_max) - int(count_SEC)))