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#F2470. Yaroslav and Permutations

    ID: 2476 传统题 2000ms 256MiB 尝试: 0 已通过: 0 难度: 2 上传者: 标签>贪心数学算法思想基础难度共享题库Codeforces英文题面题目来源题面语言

Yaroslav and Permutations

题目描述

A. Yaroslav and Permutations
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

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.

Input

The first line contains integer n (1≤n≤100) − the number of elements in the array. The second line contains n integers a1,a2,...,an (1≤ai≤1000) − the array elements.

Output

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

Examples
Input
1
1
Output
YES
Input
3
1 1 2
Output
YES
Input
4
7 7 7 7
Output
NO
Note

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.

题目来源：fps-www.educg.net-codeforce-1-2833.xml.zip；FPS 共享题包，题包内第 2105 题。保留原作者与原赛事署名。