class Flock {
  ArrayList boids;    // An arraylist for all the boids

    Flock() {
    boids = new ArrayList();              // Initialize the arraylist
  }

  void run() {    //for eaxh fish, apply the rest of the group to it.
    for (int i = 0; i < boids.size(); i++) {
      Boid b = (Boid) boids.get(i);
      b.run(boids);
    }
  }

  void addBoid(Boid b) {
    boids.add(b);
  }


}