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 C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
int main(void){

int n, i, k[100001], g[100001], h, p, q;
for(i=0; i<100001; i+=2){
 k[i]=g[i]=0;
 k[i+1]=g[i+1]=0;
}

scanf("%d", &n);
for(i=0; i<n/2; i++){
scanf("%d %d", &p, &q);
 k[p]++;
 g[q]++;
}
p=q=100001;
int memo1, memo2;
for(i=0; i<100001; i++){
 if(p>k[i]&&k[i]!=0){
  p=k[i];
  memo1=i;
 }

 if(q>g[i+1]&&g[i+1]!=0){
  q=g[i+1];
  memo2=i+1;
}
}
//printf("%d %d\n", p, q);

h=0;
if(p==n/2&&q==n/2){
 if(memo1==memo2)
  h=n/2;
 else
  h=0;
}
else{
if(p!=n/2){
 h+=p;
}


if(q!=n/2){
 h+=q;
}

}


printf("%d\n", h);
return 0;
}