let balls = [];

​

function setup() {

  createCanvas(400, 400);

}

​

function draw() {

  background(220);

  for (let i=0; i<balls.length; i++){

    balls[i].drawCircle();

    balls[i].moveCircle();

    balls[i].checkBoundary();

  }

}

​

function mousePressed(){

  balls.push(new Ball(mouseX, mouseY));

}