|시간 제한||메모리 제한||제출||정답||맞은 사람||정답 비율|
|2 초||512 MB||2||2||2||100.000%|
You have placed n distinct points on a plane. Then you will draw a half-line starting from each point in a direction chosen uniformly at random and independently from other points. Find the probability that no two half-lines will intersect.
The first line of the input contains a single integer n (2 ≤ n ≤ 5), denoting the number of points.
The i-th of the following n lines contains two integers xi and yi (−100 ≤ xi, yi ≤ 100), denoting the coordinates of the i-th point.
No two points coincide.
Display the probability that no two half-lines will have a common point. Your answer must be correct to within an absolute or relative error of 10−9.
2 0 0 1 1
3 7 8 7 7 8 8