#include #include #include #define eps 1e-6 using namespace std; struct point { int x,y; }a[10],v[10],s; double t,ans; int N,sv,i,p[10],T[3],js=1; double crosstime(double x0,double y0,double v0,double x1,double y1,double vx,double vy) { double a,b,c,t; a=vx*vx+vy*vy-v0*v0; b=2*(vx*(x1-x0)+vy*(y1-y0)); c=(x1-x0)*(x1-x0)+(y1-y0)*(y1-y0); if(a-eps) return -c/b; if(a