写出程序的运行结果
#include<iostream>
using namespace std;
class Base
{
int x;
public:
Base(int b): x(b) {}
virtual void display()
{
cout << x;
};
};
class Derived: public Base
{
int y;
public:
Derived(int d): Base(d), y(d) {} void display()
{
cout << y;
}
};
int main()
{
Base b(1);
Derived d(2);
Base *p = & d;
b.display();
d.display();
p->display();
return 0;
}
