New Year Table

题意翻译

题意：给一个大圆和一个小圆的半径，以及计划放入的小圆个数$N$，小圆必须在大圆内且与大圆相切。求是否满足。（分别输出$YES$和$NO$）。

题目描述

Gerald is setting the New Year table. The table has the form of a circle; its radius equals $ R $ . Gerald invited many guests and is concerned whether the table has enough space for plates for all those guests. Consider all plates to be round and have the same radii that equal $ r $ . Each plate must be completely inside the table and must touch the edge of the table. Of course, the plates must not intersect, but they can touch each other. Help Gerald determine whether the table is large enough for $ n $ plates.

输入输出格式

输入格式

The first line contains three integers $ n $ , $ R $ and $ r $ ( $ 1<=n<=100 $ , $ 1<=r,R<=1000 $ ) — the number of plates, the radius of the table and the plates' radius.

输出格式

Print "YES" (without the quotes) if it is possible to place $ n $ plates on the table by the rules given above. If it is impossible, print "NO". Remember, that each plate must touch the edge of the table.

输入输出样例

输入样例 #1

4 10 4

输出样例 #1

YES

输入样例 #2

5 10 4

输出样例 #2

NO

输入样例 #3

1 10 10

输出样例 #3

YES

说明

The possible arrangement of the plates for the first sample is: