第一章12.txt

本书在复习C++基础知识后

# include <iostream.h>
class B
{
		int b;
public:
		B() {}
		B(int i) { b = i;}
		virtual void virfun()
		{	cout<<“B::virfun() is called.\n”;	}
};
class D: public B
{
		int d;
		void virfun()
		{	cout<<“D::virfun() is called.\n”;	}
public:
		D() {}
		D(int i, int j): B(i)
		{ d = j; }
};
void fun(B *obj)
{	obj -> virfun();	}
int  main()
{
		D *pd = new D;		fun(pd);
		return 0;
}