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) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] array = new int[n];
        int[] guusuukou = new int[100001];
        int[] kisuukou = new int[100001];
        
        for (int i = 0; i < n; i++) {
            array[i] = sc.nextInt();
            if (i % 2 == 0) {
                guusuukou[array[i]] += 1;
            } else {
                kisuukou[array[i]] += 1;
            }
        }
        
        int guusuukouMode1 = 0;
        int guusuukouModeValue1 = 0;
        int guusuukouMode2 = -1;
        int guusuukouModeValue2 = 0;
        int kisuukouMode1 = 0;
        int kisuukouModeValue1 = 0;
        int kisuukouMode2 = -1;
        int kisuukouModeValue2 = 0;
        
        for (int i = 1; i < 100001; i++) {
            if (guusuukou[i] > guusuukouModeValue1) {
                if (guusuukouMode1 != 0) {
                    guusuukouMode2 = guusuukouMode1;
                    guusuukouModeValue2 = guusuukouModeValue1;
                }
                guusuukouMode1 = i;
                guusuukouModeValue1 = guusuukou[i];
            } else if (guusuukou[i] > guusuukouModeValue2) {
                guusuukouMode2 = i;
                guusuukouModeValue2 = guusuukou[i];
            }
            if (kisuukou[i] > kisuukouModeValue1) {
                if (kisuukouMode1 != 0) {
                    kisuukouMode2 = kisuukouMode1;
                    kisuukouModeValue2 = kisuukouModeValue1;
                }
                kisuukouMode1 = i;
                kisuukouModeValue1 = kisuukou[i];
            } else if (kisuukou[i] > kisuukouModeValue2) {
                kisuukouMode2 = i;
                kisuukouModeValue2 = kisuukou[i];
            }
        }
        
        int a;
        int b;
        
        if (guusuukouMode1 == kisuukouMode1) {
            if (guusuukouModeValue1 > kisuukouModeValue1) {
                a = guusuukouModeValue1;
                b = kisuukouModeValue2;
            } else {
                a = guusuukouModeValue2;
                b = kisuukouModeValue1;
            }
        } else {
            a = guusuukouModeValue1;
            b = kisuukouModeValue1;
        }
        
        int countToFix = n - a - b;
        System.out.println(countToFix);
        
    }
}