circleclassp.java

刘艺编著的java教程的课本习题加例题代码 很有用哦！

public class CircleClassp{
    public static void main(String args[]){
         double radius=4; 
         area(radius);
         volume(radius); 
         
    }

    public static void area(double r1) { 
        double s=3.14*r1*r1;
        display("area",s);
    }

    public static void volume(double r2) { 
        double v=3*3.14*r2*r2*r2/4; 
        display("volume",v);
    }
   
    public static void display(String st,double x) {
         System.out.println(st+"="+x);
    }
}