摘要：
Closed FencesA closed fence in the plane is a set of non-crossing, connected line segments with N corners (3 #include
#include
#include
using namespace std;
const double ex=1e-10;
const int mm=2100;
class _point
{ public:double x,y; _point(double xx,double yy){x=xx;y=yy;} _point(){}
};
class ... 阅读全文