Andy's big heart/heart.cpp

   1 #include <math.h>
   2 #include <iostream>
   3 #include <algorithm>
   4 #include <cassert>
   5
   6 #define EPSILON 0.000001
   7
   8 using namespace std;
   9
  10 struct Point{
  11   double x, y;
  12   bool operator < (const Point &p) const {
  13     return (x < p.x || (x == p.x && y < p.y));
  14   }
  15
  16   double dist(const Point &p) const {
  17     return hypot(p.x-x, p.y-y);
  18   }
  19
  20   void print(){
  21     cout << "("<<x<<","<<y<<")\n";
  22   }
  23 };
  24
  25 struct Line{
  26   double a;
  27   double b;
  28   double c;
  29   void makePointSlopeLine(Point p, double m){
  30     a = -m;
  31     b = 1;
  32     c = -((a*p.x) + (b*p.y));
  33   }
  34   bool parallel(const Line &l) const {
  35     return ((fabs(a - l.a) <= EPSILON) && (fabs(b - l.b) <= EPSILON));
  36   }
  37
  38   bool equals (const Line &l) const {
  39     return (parallel(l) && (fabs(c-l.c) <= EPSILON));
  40   }
  41
  42   Point intersection(const Line &l) const {
  43     assert( !(equals(l)) );
  44     assert( !(parallel(l)));
  45     Point r;
  46     r.x = (l.b*c - b*l.c) / (l.a*b - a*l.b);
  47     if (fabs(b) > EPSILON){
  48       r.y = - (a * r.x + c) / b;
  49     }else{
  50       r.y = - (l.a * r.x + l.c) / l.b;
  51     }
  52     return r;
  53   }
  54 };
  55
  56 int main(){
  57   Point p[3];
  58   for (int i=0; i<3; ++i){
  59     int x, y;
  60     cin >> x >> y;
  61     p[i].x = x;
  62     p[i].y = y;
  63   }
  64   while (p[0].x != 0 || p[0].y != 0 || p[1].x != 0 || p[1].y != 0 || p[2].x != 0 || p[2].y != 0){
  65     //Procesar caso aquí
  66     sort(p, p+3);
  67
  68     // for (int i=0; i<3; ++i){
  69 //       p[i].print();
  70 //     }
  71
  72
  73     Point pm1, pm2;
  74     pm1.x = (p[0].x + p[1].x) / 2.0;
  75     pm1.y = (p[0].y + p[1].y) / 2.0;
  76
  77     pm2.x = (p[1].x + p[2].x) / 2.0;
  78     pm2.y = (p[1].y + p[2].y) / 2.0;
  79
  80
  81     double m1, m2;
  82     m1 = (p[0].y - p[1].y)/(p[0].x - p[1].x);
  83     m2 = (p[1].y - p[2].y)/(p[1].x - p[2].x);
  84
  85     double pmm1 = -1/m1;
  86     double pmm2 = -1/m2;
  87     //cout << pmm1<<" "<<pmm2<<endl;
  88
  89     Line s1, s2;
  90     s1.makePointSlopeLine(pm1, pmm1);
  91     s2.makePointSlopeLine(pm2, pmm2);
  92
  93     //if (s1.parallel(s2)){
  94     if (fabs(p[0].x*(p[1].y - p[2].y) +
  95              p[1].x*(p[2].y - p[0].y) +
  96              p[2].x*(p[0].y - p[1].y)) < EPSILON){
  97       cout << "Andy's big heart will break.\n";
  98     }else{
  99       Point intersection = s1.intersection(s2);
 100       assert(intersection.dist(p[0]) - intersection.dist(p[1]) <= EPSILON);
 101       assert(intersection.dist(p[1]) - intersection.dist(p[2]) <= EPSILON);
 102       assert(intersection.dist(p[2]) - intersection.dist(p[0]) <= EPSILON);
 103              //cout << intersection.dist(p[0])<<endl;
 104              //cout << intersection.dist(p[1])<<endl;
 105              //cout << intersection.dist(p[2])<<endl;
 106
 107       printf("Andy should move to the house at point (%.3f, %.3f).\n", intersection.x, intersection.y);
 108     }
 109
 110
 111
 112
 113     //leer puntos
 114     for (int i=0; i<3; ++i){
 115       int x, y;
 116       cin >> x >> y;
 117       p[i].x = x;
 118       p[i].y = y;
 119     }
 120   }
 121   return 0;
 122 }