CIRU - The area of the union of circles
You are given N circles and expected to calculate the area of the union of the circles !
The first line is one integer n indicates the number of the circles. (1 <= n <= 1000)
Then follows n lines every line has three integers
Xi Yi Ri
indicates the coordinate of the center of the circle, and the radius. (|Xi|. |Yi| <= 1000, Ri <= 1000)
Note that in this problem Ri may be 0 and it just means one point !
The total area that these N circles with 3 digits after decimal point
0 0 1
0 0 1
100 100 1
oh, no!!! Simpson's method is too slow and eps must be carefully selected, although I got AC at the first time.