private double width; private double length; private double height;
public Rectangle(String shapeName,double l,double w,double h) {
super(shapeName); length=l; width=w; height=h; }
public double vol() {
return length*width*height; } }
public class review21 {
public static void main(String[] args) {
Shape rect =new Rectangle(\长方形\ System.out.println(\；周长=\ Shape cy=new cylinder(\圆\
System.out.println(\；周长=\ } }