3629.Yaroslav and Permutations

Time Limit: 1s Memory Limit: 256MB

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 Format(From the terminal/stdin)

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

Output Format(To the terminal/stdout)

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

Sample Input 1

Copy
1
1
 \n
 \n

Sample Output 1

Copy
YES
   \n

Sample Input 2

Copy
3
1 1 2
 \n
 · · \n

Sample Output 2

Copy
YES
   \n

Sample Input 3

Copy
4
7 7 7 7
 \n
 · · · \n

Sample Output 3

Copy
NO
  \n

Hints

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.

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