public class Ruut extends Kujund{
  protected int a;
  public Ruut(int x, int y, int a){
    super(x, y);
    this.a=a;
  }
  public double pindala(){
    return a*a;
  }
  public void joonista(java.awt.Graphics g){
    g.drawRect(x, y, a, a);
  }
}