java如何计算矩形的面积和周长？

java如何计算矩形的面积和周长？

class Ractangle { double width; double height; public Ractangle(double w,double h){ width=w; height=h; } void Area(){ System。 out。println( width*height); } void perimeter(){ System。out。println(2*(width+height)); } } public class RectangleDemo { public static void main(String args[]){ Ractangle ra...全部

  class Ractangle { double width; double height; public Ractangle(double w,double h){ width=w; height=h; } void Area(){ System。
  out。println( width*height); } void perimeter(){ System。out。println(2*(width+height)); } } public class RectangleDemo { public static void main(String args[]){ Ractangle ractangle=new Ractangle(40,50); ractangle。
  Area(); ractangle。perimeter(); } }。收起