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 OCaml (4.02.3) (judge verdict: Wrong Answer)

let () = 
	Scanf.scanf "%d" (fun n -> 
    	let whole_array = Array.init n (fun _ -> Scanf.scanf " %d" (fun x -> x))
        in 
        let list = Array.to_list whole_array in 
        let (odd_l, even_l) = 
        let rec make_l ol el l = 
        match l with
        | [] -> (ol, el)
        | x :: [] -> (x :: ol, el)
        | x :: y :: rest -> make_l (x :: ol) (y :: el) rest
        in make_l [] [] list 
        in
       (* let rec majority l *) 
       (*odd_l, even_lそれぞれについて出現回数の一番大きい数と二番目に大きい数を求める*)
       (*一番大きい数が異なれば単純にそれぞれの編集回数の和が答え。等しければ二番目を考慮*)
       
       (*以下無関係なコード*)
        let tes_sum = Array.fold_left (+) 0 whole_array in
         Printf.printf "%d" tes_sum)