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 Kotlin (1.0.0) (judge verdict: Wrong Answer)

fun main(args: Array<String>) {
    val n = readLine()!!.toInt()
    val odd = mutableListOf<Int>(); val even = mutableListOf<Int>()
    readLine()!!.split(" ").map { it.toInt() }.forEachIndexed { index, i -> 
        if (index % 2 == 0) odd.add(i) else even.add(i)
    }
    
    var o = 0; var o_c = 0
    odd.distinct().forEach {
        odd.count { i -> i == it }.let { j -> if (o_c < j) o = it; o_c = j }
    }

    var e = 0; var e_c = 0; var e_s = 0; var e_s_c = 0
    even.distinct().forEach {
        even.count { i -> i == it }.let { j ->
            if (e_c < j) {
                e = it; e_c = j
            } else if (e_s_c < j) {
                e_s = it; e_s_c = j
            }
        }
    }
    
    if (o != e) {
        println(((n / 2) - o_c) + (n / 2) - e_c)
    } else println(((n / 2) - o_c) + (n / 2) - e_s_c)
    
}