304301: CF820B. Mister B and Angle in Polygon
Memory Limit:256 MB
Time Limit:2 S
Judge Style:Text Compare
Creator:
Submit:0
Solved:0
Description
Mister B and Angle in Polygon
题意翻译
### 题目描述 在一个边为 $n$ 的正凸多边形上,有一个角 $a$。 现在要找到三个不同的顶点 $v1$ , $v2$ , $v3$ 使得 $∠ v1 v2 v3$ (其中 $v2$ 是角度的顶点,并且 $v1$ 和 $v3$ 位于其两侧)尽可能接近 $a$(换句话说,该值应该尽可能小)。 如果有多个最优解,可以输出**任意一个**。 ### 输入格式 一行包含两个空格分隔的整数 $n$ 和 $a$ ( $3<=n<=10^{5}$ , $1<=a<=180$) $n$ 表示多边形中的顶点数,$a$表示所需的角度,以度为单位。 ### 输出格式 输出三个空格分隔的整数:$∠ v1 v2 v3$ 的顶点 $v1$ , $v2$ , $v3$ 。如果有多个最优解,输出其中**任意一个**。 顶点按**顺时针**顺序从 $1$ 到 $n$ 编号。题目描述
On one quiet day all of sudden Mister B decided to draw angle $ a $ on his field. Aliens have already visited his field and left many different geometric figures on it. One of the figures is regular convex $ n $ -gon (regular convex polygon with $ n $ sides). That's why Mister B decided to use this polygon. Now Mister B must find three distinct vertices $ v_{1} $ , $ v_{2} $ , $ v_{3} $ such that the angle ![](https://cdn.luogu.com.cn/upload/vjudge_pic/CF820B/6d6c5a52027f58c108350561b7ff23e63c6d24de.png) (where $ v_{2} $ is the vertex of the angle, and $ v_{1} $ and $ v_{3} $ lie on its sides) is as close as possible to $ a $ . In other words, the value ![](https://cdn.luogu.com.cn/upload/vjudge_pic/CF820B/1f65cda47093761b7aa9cbd2b73454017bbcd824.png) should be minimum possible. If there are many optimal solutions, Mister B should be satisfied with any of them.输入输出格式
输入格式
First and only line contains two space-separated integers $ n $ and $ a $ ( $ 3<=n<=10^{5} $ , $ 1<=a<=180 $ ) — the number of vertices in the polygon and the needed angle, in degrees.
输出格式
Print three space-separated integers: the vertices $ v_{1} $ , $ v_{2} $ , $ v_{3} $ , which form ![](https://cdn.luogu.com.cn/upload/vjudge_pic/CF820B/6d6c5a52027f58c108350561b7ff23e63c6d24de.png). If there are multiple optimal solutions, print any of them. The vertices are numbered from $ 1 $ to $ n $ in clockwise order.
输入输出样例
输入样例 #1
3 15
输出样例 #1
1 2 3
输入样例 #2
4 67
输出样例 #2
2 1 3
输入样例 #3
4 68
输出样例 #3
4 1 2