I have this code almost finished, but I am stuck at one part. I don't understand how to make the balloon disappear when the mouse is over the balloon. Here is some information, http://evc-cit.info/cit020/arrays.html

Here is my code;
Balloon [] balloons = new Balloon[30];

void setup()
{
  float x;
  float y;
  float w;
  float h;
  color c;
  size(400, 400);
  frameRate(20);
  for (int i = 0; i < balloons.length; i++)
  {
    w = random(20, 45);
    h = w + random(5, 10); /* h = random(25, 55); // doesn't work */
    x = random(w/2, width-w/2);/* so that balloon is on screen */
    y = random(h/2, height-h/2);/* so that balloon is on screen */
    c = color(random(255), random(255), random(200), random(128, 200));
    balloons[i] = new Balloon(x, y, w, h, c);/* random color */
  }
}
void draw()
{
  background(255);
  for (int i = 0; i < balloons.length; i++)
  {
    if (balloons[i].hit(mouseX, mouseY)) // the parameters will be the point we want to test to see if it's "inside"
    }
else
{
 

  balloons[i].display();
  balloons[i].move(); //move the balloon at index number i*/

  // if the mouse "hits" balloon at index number i
  //   then pop balloon at index number i
}
}


class Balloon
{
  float x;
  float y;
  float w;
  float h;
  color c;
  float xSpeed;
  float ySpeed;

  Balloon(float bx, float by, float bw, float bh, color bc)
  {
    x = bx;
    y = by;
    w = bw;
    h = bh;
    c = bc;
    xSpeed = 3;
    ySpeed = 7;
  }

  void display()
  {
    fill(c, 150);
    ellipse(x, y, w, h);
  }

  boolean hit (int pX, int pY)
  {
    float a = w / 2.0;
    float b = h / 2.0;
    float ex = pX - x; // calculate relative to center of ellipse
    float ey = pY - y;
    float r = (ex * ex) / (a * a) + (ey * ey) / (b * b);
    return (r < 1);
  }

  void pop()
  {
    x= -1000;
    y= -1000;
    xSpeed = 0;
    ySpeed = 0;
  }
 
  void move()
  {
    x += xSpeed;
    if (x < w/2 || x > width-w/2)
    {
      xSpeed = -xSpeed;
    }

    y += ySpeed;
    if (y < h/2 || y > height-h/2)
    {
      ySpeed = -ySpeed;
    }
  }
}