public class TwoPointGame {

  public static void main (String[] argv)
  {
    try {
      if ( (argv == null) || (argv.length != 2) ) {
        System.out.println ("Usage: TwoPointGame <numGames> <R>");
        System.exit(1);
      }

      int numGames = Integer.parseInt (argv[0]);
      double R = Double.parseDouble (argv[1]);
      
      playGames (numGames, R);
    }
    catch (Exception e) {
      e.printStackTrace();
    }
  }

  static double totalDist = 0;


  public static void playGames (int numGames, double R)
  {
    int numA_wins = 0,  numB_wins = 0;
    totalDist = 0;
    
    for (int i=0; i<numGames; i++) {

      // Play a game.
      boolean A_wins = playGame (R);

      if (A_wins) {
        numA_wins ++;
      }
      else {
        numB_wins ++;
      }
      
    }
    
    // Results.
    double fracA_wins = (double) numA_wins / numGames;
    double fracB_wins = (double) numB_wins / numGames;
    System.out.println ("Fraction of games won by A: " + fracA_wins);
    System.out.println ("Fraction of games won by B: " + fracB_wins);
    System.out.println ("Average distance: " + (totalDist / numGames));
  }
  

  public static boolean playGame (double R)
  {
    // Generate two points randomly in the unit square.
    double x1 = UniformRandom.uniform();
    double y1 = UniformRandom.uniform();
    double x2 = UniformRandom.uniform();
    double y2 = UniformRandom.uniform();

    // Compute the distance between them.
    double dist = Math.sqrt ( (x1-x2)*(x1-x2) + (y1-y2)*(y1-y2) );

    // Accumulate total distance (for observation purposes).
    totalDist += dist;
    
    // See if A wins.
    if (dist < R)
      return true;
    else
      return false;
  }
  

}