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 Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.*;
public class Main{
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        
        int times = sc.nextInt();
        int [] first = new int[times/2];
        int [] second = new int[times/2];
        int result =0;
        int k = 0 ;
        int n = 0;
        for(int i = 0 ; i<times; i++){
            if(i%2==0){
                first[k] = sc.nextInt();
                k++;
            }
            else{
                second[n] = sc.nextInt();
                n++;
            }
        }
        
        boolean test = true;
        
        if(first[0]==second[0]){
            System.out.println(times/2);
            test = false;
        }
        
        for(int i = 0 ; i<(times/2) ; i++){
            if(first[i]!=first[0] || second[i]!=second[0]){
                result++;
            }
        }
        
        if(test !=false){
            System.out.println(result);    
        }
        
        
    }
}