/*
 * File: PiApproximation.java
 * --------------------------
 * This progam computes an approximation to pi by simulating
 * a dart board, as described in the handout.  The general
 * technique is called Monte Carlo integration.
 *
 * Author: CS1MD3, Nov. 2008
 */

import acm.program.*;
import acm.util.*;

public class PiApproximation extends ConsoleProgram {

   public void run() {
      int inside = 0;
      for (int i = 0; i < NDARTS; i++) {
         double x = rgen.nextDouble(-1.0, +1.0);
         double y = rgen.nextDouble(-1.0, +1.0);
         if (x * x + y * y < 1.0) inside++;
      }
	    double pi = 4.0 * inside / NDARTS;
	    println("Pi is approximately " + pi);
   }

/* Private constant */
   private static final int NDARTS = 10000;  /* Number of darts to throw */

/* Private instance variables */
   private RandomGenerator rgen = RandomGenerator.getInstance();

}