Java_静态变量

class c1c {
    private static int num = 0;
    private static double pi = 3.14;
    private double radius;
    private int height;
    public c1c(double r,int h)
    {
        radius = r;
        height=h;
        num++;
    }
    public void count()
    {
        System.out.print("创建了"+num+"个对象");
    }
    double area() {
        return pi*radius*radius;
    }
    double volume() {
        return area()*height;
    }
}
public class cc{
    public static void main(String[] args)
    {
        c1c volu1=new c1c(2.5,5);
        volu1.count();
        System.out.println("圆柱1的体积="+volu1.volume());
        c1c volu2=new c1c(1.0,2);
        volu2.count();
        System.out.println("圆柱2的体积="+volu2.volume());
    }
}

private int num = 0;