#include<iostream>
#include<stdlib.h>
#include<time.h>
using namespace std;

/* Calcul de la proportion d'une surface recouverte par des pieces lancees */

const int N_pieces = 10, N_points = 10000, N_fois = 100;
const double rayon = 0.1;

int main(){
  int i, j, k, c;
  double xx, yy, d2, r, rr;
  double *x, *y;

  srand48(time(NULL));
  x = (double*)malloc(N_pieces * sizeof(double));
  y = (double*)malloc(N_pieces * sizeof(double));
  rr = 0.;
  for (i = 0; i < N_fois; i++){
    for (k = 0; k < N_pieces; k++){
      x[k] = rayon + (1.-2*rayon)*drand48();
      y[k] = rayon + (1.-2*rayon)*drand48();
    }
    c = 0;
    for (j = 0; j < N_points; j++){
      xx = drand48();
      yy = drand48();
      for (k = 0; k < N_pieces; k++){
	d2 = (xx-x[k])*(xx-x[k]) + (yy-y[k])*(yy-y[k]);
	if (d2 <= rayon*rayon){
	  c++;
	  break;
	}
      }
    }
    r = (double)c / N_points;
    cout << r << endl;
    rr += r;
  }
  cout << "La proportion moyenne occupee par " << N_pieces 
       << " pieces avec rayon " << rayon << " est : " << rr / N_fois << endl;
  free(x);
  free(y);
  return 0;
}