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 Go (1.6) (judge verdict: Wrong Answer)

// Package main provides
//
// File:  c.go
// Author: ymiyamoto
//
// Created on Sat Dec  1 15:43:49 2018
//
package main

import "fmt"

var n int

func max(x []int, exception int) (int, int) {
	val := 0
	index := 0

	for i, n := range x {
		if i != exception && val < n {
			val = n
			index = i
		}
	}

	return index, val
}

func main() {
	fmt.Scan(&n)

	count1 := make([]int, 1e5+1)
	count2 := make([]int, 1e5+1)

	for i := 0; i < n; i++ {
		var v int
		fmt.Scan(&v)
		if i%2 == 0 {
			count1[v]++
		} else {
			count2[v]++
		}
	}

	val1, c1 := max(count1, 0)
	_, c2 := max(count2, val1)

	fmt.Println(n - c1 - c2)
}