Yaroslav and Permutations

题意翻译

你有一个数组，现在你要在有限的次数内移动相邻的两个数，最后是否能使数组中没有数字相同的相邻元素。

题目描述

Yaroslav has an array that consists of $ n $ integers. In one second Yaroslav can swap two neighboring array elements. Now Yaroslav is wondering if he can obtain an array where any two neighboring elements would be distinct in a finite time. Help Yaroslav.

输入输出格式

输入格式

The first line contains integer $ n $ $ (1<=n<=100) $ — the number of elements in the array. The second line contains $ n $ integers $ a_{1},a_{2},...,a_{n} $ $ (1<=a_{i}<=1000) $ — the array elements.

输出格式

In the single line print "YES" (without the quotes) if Yaroslav can obtain the array he needs, and "NO" (without the quotes) otherwise.

输入输出样例

输入样例 #1

1
1

输出样例 #1

YES

输入样例 #2

3
1 1 2

输出样例 #2

YES

输入样例 #3

4
7 7 7 7

输出样例 #3

NO

说明

In the first sample the initial array fits well. In the second sample Yaroslav can get array: $ 1 $ , $ 2 $ , $ 1 $ . He can swap the last and the second last elements to obtain it. In the third sample Yarosav can't get the array he needs.