Calculating the volume of balls in jeliot

This is a program to find the area of ​​a sphere in the form jeliot,,,
How it works almost the same as in dev c + + or anything, but jeliot will be easier in understanding, using a visual, so that each step in the workmanship we can see and also how eksekusinnya. And we also do not need to imagine how it works,,,

import jeliot.io.*;

public class luas {

    public static void main()

     {

     int r;

     float luas;

     System.out.print("Masukan Jari-jari");

     r = Input.readInt();

     luas = (float)3.14*r*r;

     System.out.print("Luas lingkaran :");

     System.out.print(luas);

     float volum;

     volum = (float)4/3* (float)3.14*r*r;

     System.out.print("volum bola :");

     System.out.print(volum);  

    }

}