引用静态数据成员

#include <iostream>

/* run this program using the console pauser or add your own getch, system("pause") or input loop */
using namespace std;
class Box
{
    public:
        Box(int,int);
        int volume();
        static int height;
        int width;
        int length;
};

Box::Box(int w ,int len)
{
    width=w;
    length=len;
}

int Box::volume()
{
    return(height*width*length);
}
int Box::height=10;

int main(int argc, char** argv) {
    Box a(15,20),b(20,30);
    cout<<a.height<<endl;
    cout<<b.height<<endl;
    cout<<Box::height<<endl;
    cout<<a.volume()<<endl;
    return 0;
}