Heavenly Jewels
Time limit2sMemory limit512 MB
Given three fixed points in a 10000 by 10000 square, find the area where IC's point is the last-nearest among the three, divided by the square's area.
- Level
Medium7 of 10
- Topics
- Geometry, Math, Implementation
- Solved
- No attempts yet
Problem
There is an island whose shape is a perfect square. On this island live three inhabitants named IC, PC, and ACM. Every day, one jewel is dropped from the sky. Just as the jewel touches the ground, IC, PC, and ACM leave their houses simultaneously, run at the same speed, and the person who first touches the jewel gets it. Hence, the person whose house is nearest to the location of the jewel is the winner of that day.
They always quarrel with each other, so their houses are located at distinct places. The locations of their houses are fixed. This jewel falls at a random point on the island, that is, all points on the island have equal chance.
When there are two or more persons whose houses are simultaneously nearest, the last person in the order of
IC, PC, ACM
obtains the jewel. Our interest is to know the probability for IC to get the jewel under this situation.
Input
The input describes one problem instance per line. Each line contains the x- and y-coordinates of IC's home, those of PC's, and those of ACM's in this order. Note that the houses of IC, PC, and ACM are located at distinct places. The end of the input is indicated by a line with six zeros.
The coordinates of the whole island are given by (0, 10000)(0, 10000) and coordinates of houses are given in integer numbers between 1 and 9999; inclusive. It should be noted that the locations of the jewels are arbitrary places on the island and their coordinate values are not necessarily integers.
Output
For each input line, your program should output its sequence number starting from 1, and the probability for the instance. The computed probability values should have errors less than 10-5.
The sequence number and the probability should be printed on the same line. The two numbers should be separated by a space.