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)

n = int(input())
V = [int(v) for v in input().split(' ')]

even_map = {}
odd_map = {}

for i in range(0, n, 2):
    v = V[i]
    if not v in even_map:
        even_map[v] = 1
    else:
        even_map[v] += 1


for i in range(1, n, 2):
    v = V[i]
    if not v in odd_map:
        odd_map[v] = 1
    else:
        odd_map[v] += 1

even_n = -1
odd_n = -1
max_value = 0
for key, value in even_map.items():
    if max_value < value:
        max_value = value
        even_n = key

for key, value in odd_map.items():
    if max_value < value:
        max_value = value
        odd_n = key

max_even = 0
max_odd = 0
if odd_n >= 0:
    max_odd = max_value
    max_value = 0
    for key, value in even_map.items():
        if key == odd_n:
            continue
        if max_value < value:
            max_value = value
            even_n = key
    max_even = max_value

else:
    max_even = max_value
    max_value = 0
    for key, value in odd_map.items():
        if key == even_n:
            continue
        if max_value < value:
            max_value = value
            odd_n = key
    max_odd = max_value

print(n - (max_even + max_odd))