#include #include #include #include using namespace std; const double pi=acos(-1.0); const int maxn=1005; double x[maxn], y[maxn]; int n; double dis2 (double x1,double y1 ,double x2,double y2) { double tmp1=x1-x2,tmp2=y1-y2; tmp1*=tmp1; tmp2*=tmp2; return tmp1+tmp2; } double test(double xx, double yy) { double max = 0,tmp; for (int i=0;i0.001 ; delta*=0.9) { for (theta=0 ; theta<=2*pi ; theta+=(pi/25.0)) { double tx=xx+delta*cos(theta); double ty=yy+delta*sin(theta); double tdis=test(tx,ty); if(tdis