201030: [AtCoder]ARC103 C - ////

Memory Limit:1024 MB Time Limit:2 S
Judge Style:Text Compare Creator:
Submit:1 Solved:0

Description

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 /\/\/\/.

Input

题意翻译

给定一个偶数长度的序列 $\{a_n\}$,定义「合法」表示 $\forall i<n-1,a_{i}=a_{i+2}$ 。 定义操作:每次选择一个数替换掉某个位置。 求最少需要操作多少次使得序列合法。 $1\leq n\leq 100000,1\leq a_i\leq 100000$。 注:两个序列中的数字不能相同。

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