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 PyPy3 (2.4.0) (judge verdict: Accepted)

# import bisect
from collections import Counter, deque
# import copy
# from fractions import gcd
# from functools import reduce
# from itertools import accumulate, permutations, combinations, combinations_with_replacement, groupby, product
# import math
# import numpy as np
import sys
sys.setrecursionlimit(10 ** 5 + 10)
# input = sys.stdin.readline

def resolve():
    n=int(input())
    V=list(map(int,input().split()))

    E=[]
    O=[]

    for i in range(n):
        if i%2==0:
            E.append(V[i])
        else:
            O.append(V[i])

    e=Counter(E)
    o=Counter(O)

    if e.most_common()[0][0] != o.most_common()[0][0]:
        print(n-e.most_common()[0][1]-o.most_common()[0][1])
    else:
        if len(e.most_common()) ==1:
            if  len(o.most_common())==1:
                print(n//2)
            else:
                print(n-e.most_common()[0][1]-o.most_common()[1][1])
        elif len(o.most_common())==1:
            print(n - e.most_common()[1][1] - o.most_common()[0][1])
        else:
            print(min(n-e.most_common()[1][1]-o.most_common()[0][1], \
                      n-e.most_common()[0][1]-o.most_common()[1][1]))

resolve()