Counting Self-Rotating Subsets
Time limit2sMemory limit512 MB
For each size i, count the subsets of the given N points that a nontrivial rotation maps onto themselves, modulo 1e9+7.
- Level
Hard8 of 10
- Topics
- Geometry, Combinatorics
- Solved
- No attempts yet
Problem
A set of points in the plane is self-rotating if there is a point and an angle in degrees with such that rotating the plane around by sends every point of the set to a point that also belongs to the set. The point is the center of the rotation.
You are given a set of distinct points whose coordinates are integers. For each size , count the subsets of that size that are self-rotating. Two subsets are different when one of them contains a point that the other does not contain.
Input
The first line contains one integer , the number of points ().
Each of the next lines contains two integers and , the coordinates of one point (). The given points are all distinct.
Output
Print one line with integers separated by single spaces. is the number of self-rotating subsets that contain exactly points. These counts can be very large, so print each one modulo .