UVa/10310 - Dog and Gopher/p10310.cpp

   1 #include <iostream>
   2 #include <math.h>
   3
   4 using namespace std;
   5
   6 int main(){
   7   int n;
   8   double gx, gy, dx, dy;
   9   while (cin >> n >> gx >> gy >> dx >> dy){
  10     bool escaped = false;
  11
  12
  13     for (int i=0; i<n; ++i){
  14
  15       double hx, hy;
  16       cin >> hx >> hy;
  17       if (!escaped){
  18         double d, g;
  19         g = sqrt(pow(gx - hx,2)+pow(gy - hy,2));
  20         d = sqrt(pow(dx - hx,2)+pow(dy - hy,2));
  21         if (g*2 <= d){
  22           escaped = true;
  23           printf("The gopher can escape through the hole at (%.3f,%.3f).\n", hx, hy);
  24         }
  25       }
  26     }
  27     if (!escaped) cout << "The gopher cannot escape.\n";
  28
  29   }
  30
  31   return 0;
  32 }