box program

class box
{
double width;
double height;
double depth;

box(box o)
{
width=o.width;
height=o.height;
depth=o.depth;
}

box(double w,double h,double d)
{
width=w;
height=h;
depth=d;
}
box()
{
width=20;
height=40;
depth=50;
}
box(double x)
{
width=height=depth=x;
}
double volume()
{
return width*height*depth;
}
}

class conoap
{
public static void main(String args[])
{
box mybox1=new box(10,40,20);
box mybox2=new box();
box mycube=new box(8);
box myref=new box(mybox1);
double vol;
vol=mybox1.volume();
System.out.println(vol);

vol=mybox2.volume();
System.out.println(vol);

vol=mycube.volume();
System.out.println(vol);

vol=myref.volume();
System.out.println(vol);
}
}