prog3.cpp

来自「C++语言程序设计题典」· C++ 代码 · 共 61 行

#include <iostream.h>
class A
{
protected:
	char ver;
public:
	A() { ver='A'; }
	virtual void print()
	{
		cout << "The A version:" << ver << endl;
	}
};
class B1:public A
{
	int info;
public:
	B1(int n) { info=n;ver='1'; }
	void print()
	{
		cout << "The B1 info:" << info << " version " << ver << endl; 
	}
};
class B2:public A
{
	int info;
public:
	B2(int n) { info=n; }
	void print()
	{
		cout << "The B2 info:" << info << " version " << ver << endl; 
	}
};
class C:public B1
{
	int info;
public:
	C(int n):B1(n)
	{
		info=n;ver='3';
	}
	void print()
	{
		cout << "The C info:" << info << " version " << ver << endl; 
	}
};
void print_info(A *p)
{
	p->print();
}
void main()
{
	A a;
	B1 b1(10);
	B2 b2(20);
	C c(30);
	print_info(&a);
	print_info(&b1);
	print_info(&b2);
	print_info(&c);
}