因Blog內定文章格式關係，故以"囗"為空格請自行修改回去！
class AddDoubles {
囗囗public static void main (String args[]) {
囗囗囗囗double x = 7.5;
囗囗囗囗double y = 5.4;
囗囗囗囗double z;
囗囗囗囗System.out.println("x is " + x);
囗囗囗囗System.out.println("y is " + y);
囗囗囗囗z = x + y;
囗囗囗囗System.out.println("x + y is " + z);
囗囗囗囗z = x - y;
囗囗囗囗System.out.println("x - y is " + z);
囗囗}
囗}
