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: Wrong Answer)

n = int(input())
v = list(map(int,input().split()))

v1 = []
v2 = []
for i in range(n):
    if i%2 == 0:
        v1.append(v[i])
    else:
        v2.append(v[i])
v1.sort()
v2.sort()

v1num = []
v2num = []
cnt1 = []
cnt2 = [] 
for x in v1:
    if x not in v1num:
        v1num.append(x)
        cnt1.append(1)
    else:
        cnt1[-1] += 1
for x in v2:
    if x not in v2num:
        v2num.append(x)
        cnt2.append(1)
    else:
        cnt2[-1] += 1
#print(v1num,v2num,cnt1,cnt2)

res = 0
m1 = max(cnt1)
m2 = max(cnt2)
maxc1ind = cnt1.index(m1)
maxc2ind = cnt2.index(m2)
maxc1 = v1num[maxc1ind]
maxc2 = v2num[maxc2ind]
if maxc1 != maxc2:
    res = n - m1 - m2
else:
    if len(cnt1) == 1 and len(cnt2) == 1 and maxc1 == maxc2:
        res = n // 2
    else:    
        if m1 > m2:
            cnt2.sort(reverse=True)
            res = n - m1 - cnt2[1]
        else:
            cnt1.sort(reverse=True)
            res = n - m2 - cnt1[1]
print(res)