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)

# 初期入力
from collections import Counter
import sys
input = sys.stdin.readline  #文字列では使わない
n = int(input())
v = list(map(int, input().split()))
vo1 =v[1::2]
ve2 =v[0::2]
co1_k,co1_v = zip(*Counter(vo1).most_common())
ce2_k,ce2_v = zip(*Counter(ve2).most_common())
"""
co1_l =list(co1.values())
ce2_l =list(ce2.values())
co1_l.sort(reverse=True)
ce2_l.sort(reverse=True)
"""
ans =0

if vo1 ==ve2:
    ans =len(vo1)
elif len(co1_v) ==len(ce2_v) ==1:
    ans =0
elif co1_k[0] ==ce2_k[0]:
    if len(co1_v) ==1:
        ans =sum(ce2_v[1:])
    elif len(ce2_v) ==1:
        ans =sum(co1_v[1:])
    elif len(co1_v) ==len(ce2_v) ==2:
        ans1 =co1_v[1] +ce2_v[0]
        ans2 =co1_v[0] +ce2_v[1]
        ans =min(ans1,ans2)
    elif len(co1_v) ==2:
        ans1 =co1_v[1] +ce2_v[0] +sum(ce2_v[2:])
        ans2 =co1_v[0] +sum(ce2_v[1:])
        ans =min(ans1,ans2)
    elif len(ce2_v) ==2:
        ans1 =ce2_v[1] +co1_v[0] +sum(co1_v[2:])
        ans2 =ce2_v[0] +sum(co1_v[1:])
        ans =min(ans1,ans2)
    else:
        ans1 =sum(co1_v[1:]) +ce2_v[0] +sum(ce2_v[2:] )
        ans1 =sum(ce2_v[1:]) +co1_v[0] +sum(co1_v[2:] )
        ans =min(ans1,ans2)
else: 
    if len(co1_v) ==1:
        ans =sum(ce2_v[1:])
    elif len(ce2_v) ==1:
        ans =sum(co1_v[1:])
    else:
        ans =sum(co1_v[1:]) +sum(ce2_v[1:])  
   
print(ans)