程序填空_2

源程序：

#include <iostream>
using namespace std;

class Person
{
public:
virtual void disp()
{
cout<<"Person ";
}
};
class Address:public Person //程序填空
{
public:
void disp()
{
cout<<"Address"<<endl;
}
};

class PhoneNumber:public Person
{
public:
void disp()
{
cout<<"PhoneNumber"<<endl;
}
};
void main()
{
Person *p;
Address a;
PhoneNumber pn;
p=&a;
p->Person::disp(); //显示Person
p->disp(); //显示Address
p=&pn;
p->Person::disp(); //程序填空 显示Person
p->disp(); //显示PhoneNumber
}

 结果：