1 #include<stdio.h>
  2 #include<string.h>
  3 #include<stdlib.h>
  4 #include<math.h>
  5 const int MAX=0x3f3f3f3f ;
  6 const double esp = 1e-7;
  7 
  8 struct Tnode
  9 {
 10   double x,y;
 11 }w1,w2,t1,t2;
 12 double vw,vt,dl,du;
 13 double getmin(double a , double b)
 14 {
 15   return (a>b)?b:a;
 16 }
 17 //求点积
 18 double dianji(Tnode &a ,Tnode &b ,Tnode &c)
 19 {
 20    return (b.x-a.x)*(c.x-a.x)+(b.y-a.y)*(c.y-a.y);
 21 }
 22 //求叉 积
 23 double det(Tnode &a ,Tnode &b ,Tnode &c)
 24 {
 25   return (b.x-a.x)*(c.y-a.y)-(c.x-a.x)*(b.y-a.y);
 26 }
 27 //求距离
 28 double  dis(Tnode &a,Tnode &b)
 29 {
 30   return sqrt(fabs((b.x-a.x)*(b.x-a.x)+(b.y-a.y)*(b.y-a.y)));
 31 }
 32 //求点o到线段的最近的距离
 33 double getdistance(Tnode &o,Tnode a ,Tnode b,double dx,double dy)
 34 {
 35     a.x+=dx;
 36     a.y+=dy;
 37     b.x+=dx;
 38     b.y+=dy;
 39     double d =getmin(dis(o,a),dis(o,b));
 40     double di=dis(a,b);
 41     if(di<=esp) return dis(o,a);
 42     if(dianji(a,o,b)>=-esp&&dianji(b,o,a)>=-esp)
 43         return  fabs(det(a,b,o))/di;
 44     else
 45         return  getmin(dis(o,a),dis(o,b));
 46 }
 47 //求o到以线段ab为起始，(dx,dy)为间距的平行线段的最近距离
 48 double calc(Tnode &o ,Tnode &a ,Tnode &b , double dx, double dy)
 49 {
 50     Tnode a1,b1;
 51     int ll=0,rr=MAX;
 52     while(ll<rr)
 53     {
 54         int mid=(ll+rr)/2;
 55         double d1=getdistance(o,a,b,dx*mid,dy*mid);
 56         double d2=getdistance(o,a,b,dx*(mid+1),dy*(mid+1));
 57         if(d1<d2+esp) rr=mid;
 58         else ll=mid+1;
 59     }
 60     return getdistance(o,a,b,dx*ll,dy*ll);
 61 }
 62 void work()
 63 {
 64   Tnode wdr ,tdr,move,a1,b1,a2,b2;
 65   double distance,time,d,d1,d2;
 66   distance=dis(w1,w2);
 67   wdr.x = (w2.x-w1.x)*vw/distance;
 68   wdr.y = (w2.y-w1.y)*vw/distance;
 69   distance = dis(t1,t2);
 70   time = distance/vt;
 71   tdr.x = (t2.x-t1.x)*vt/distance;
 72   tdr.y=(w2.y-w1.y)*vt/distance;
 73    move.x=(-wdr.x+tdr.x)*time;
 74    move.y=(-wdr.y-tdr.y)*time;
 75  //求两个线段簇的第一条线段a1-b1和a2-b2
 76   a1=t1;
 77   b1.x=a1.x+move.x;
 78   b1.y=a1.y+move.y;
 79   move.x=(-wdr.x+tdr.x)*time;
 80   move.y=(-wdr.y+tdr.y)*time;
 81   a2=b1;
 82   b2.x=a2.x+move.x;
 83   b1.y=a1.y+move.y;
 84   //分别求点w1到两个线段簇的最近距离d1和d3
 85   d1=calc(w1,a1,b1,b2.x-a1.x,b2.y-a1.y);
 86   d2=calc(w1,a2,b2,b2.x-a1.x,b2.y-a1.y);
 87  //判断结果
 88    d=getmin(d1,d2);
 89    if(d+esp<d1)  printf("Dangerous\n");
 90     else if(d-esp>du)
 91       printf("Miss\n");
 92       else 
 93         printf("Perfect\n");
 94 }
 95 int main()
 96 {
 97     while(scanf("%lf",&w1.x)!=EOF)
 98     {
 99         scanf("%lf%lf%lf%lf",&w1.y,&w2.x,&w2.y,&vw);
100         scanf("%lf%lf%lf%lf%lf",&t1.x,&t1.y,&t2.x,&t2.y,&vt);
101         scanf("%lf%lf",&dl,&du);
102         work();
103     }
104    return 0;
105 }