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 PHP7 (7.0.15) (judge verdict: Wrong Answer)

<?php
$n=trim(fgets(STDIN));
$v=explode(" ",trim(fgets(STDIN)));
$i=0;
while($i<$n){
    $e[]=$v[$i];
    $o[]=$v[$i+1];
    $i+=2;
}
$e=array_count_values($e);
$o=array_count_values($o);
if(key($e)!=key($o)){
    echo $n-reset($e)-reset($o);
}else{
    if($n/2 == reset($e)){
        echo $n/2 - next($o);
    }elseif($n/2 == reset($o)){
        echo $n/2 - next($e);
    }else{
        if(reset($e)>=reset($o)){
            echo $n-reset($e)-next($o);
        }else{
            echo $n-reset($o)-next($e);
        }
    }
}