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 (3.8.2) (judge verdict: Runtime Error)

from collections import Counter

n, *v = map(int, open(0).read().split())
vo = Counter(v[::2])
ve = Counter(v[1::2])
vo_mc = vo.most_common()[0]
ve_mc = ve.most_common()[0]
if vo_mc[0] == ve_mc[0]: 
    if vo_mc[1] > ve_mc[1]:
        ans = n//2 - vo_mc[1]
        if ve_mc[1] != n//2:
            ans += n//2 - ve.most_common()[1][1]
        else:
            ans += n//2
    elif vo_mc[1] < ve_mc[1]:
        ans =  n//2 - ve_mc[1]
        if vo_mc[1] != n//2:
            ans += n//2 - vo.most_common()[1][1]
        else:
            ans += n//2
else:
    ans = n//2 - vo_mc[1] + n//2 - ve_mc[1]
print(ans)