P2950 [USACO09OPEN] Bovine Embroidery G
题目描述
Bessie has taken up the detailed art of bovine embroidery. Cows embroider a cloth mounted in a circular hoop of integer radius d (1
输入格式
\* Line 1: Two space-separated integers: N and d
\* Lines 2..N+1: Line i+1 describes thread i with three integers: a, b, and c
输出格式
\* Line 1: One integer, on a line by itself, that is the count of pairs of threads that intersect.
说明/提示
The two lines are x=0 and y=0.
The two lines intersect at (0,0), which is clearly with 1 of the origin.