exam0-6.cpp

一个简单的数值计算程序所使用的数据是一些实数或整数

#include <iostream.h>

class Parent
{
protected:
	char version;
public:
	Parent(){version = 'A';}					   		//构造函数
//	virtual void Print()							//虚函数
	void Print()							//虚函数
		{cout << "Version of parent is: " << version << endl;}
};

class Derived1: public Parent
{
private:
	int info;
public:
	Derived1(int number)				   //构造函数
		{version = 'B';  info = number; }			//注意此时version属性由不同的值
	void Print()
		{cout << "Version and info of Derived1 is: " << version << info << endl;}
};

class Derived2: public Parent
{
private:
	int info;
public:
	Derived2(int number)				   //构造函数
		{version = 'C';  info = number; }			//注意此时version属性由不同的值
	void Print()
		{cout << "Version and info of Derived2 is: " << version << info << endl;}
};

void PrintInfo(Parent &infoHolder)
{
	infoHolder.Print();	//根据不同的调用对象动态连接不同对象的成员函数
}

void main(void)
{
	Parent base;
	Derived1 d1(10);
	Derived2 d2(20);

	PrintInfo(base);
	PrintInfo(d1);
	PrintInfo(d2);
}