Ball b1, b2, b3;
Ball[] balls;

void setup() {
   size(500, 500);
   background(255);
   
   b1 = new Ball();
   b2 = new Ball();
   b3 = new Ball();
   
   balls = new Ball[10];
   for (int i = 0; i < balls.length; i++) {
      balls[i] = new Ball(random(5, 25));
   }
   
} // setup()

void draw() {
   b1.display();
   b2.display();
   b3.display();
   
   for (int i = 0; i < balls.length; i++) {
      balls[i].display();
   }
} // draw()