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

even = {}
odd = {}


for i in range(N):
    if(i%2==0):
        if odd.get(V[i],None)==None:
            odd[V[i]]=1
        else:
            odd[V[i]]+=1
    else:
        if even.get(V[i],None)==None:
            even[V[i]]=1
        else:
            even[V[i]]+=1


max_odd_k = max(odd, key=odd.get)
max_even_k = max(even, key=even.get)
max_odd_v = max(odd.values())
max_even_v = max(even.values())
len_odd = len(odd)
len_even = len(even)

if(max_odd_k!=max_even_k):
    print(N-max_odd_v-max_even_v)
    exit()

if((len_odd==1)&(len_even==1)):
    print(N//2)
    exit()


if(len_odd==1):
    del even[max_even_k]
    max_even_k = max(even, key=even.get)
    max_even_v = max(even.values())
    print(N-max_odd_v-max_even_v)
    exit()

if(len_even==1):
    del odd[max_odd_k]
    max_odd_k = max(odd, key=odd.get)
    max_odd_v = max(odd.values())
    print(N-max_odd_v-max_even_v)
    exit()

#print()