C++虚函数与多态——马会飞

根据以下主函数完善程序内容，以实现规定的输出。不允许改变主函数的内容。

int main()
{
	Horse *p1 = new Horse; //输出：Horse 申请了空间...
	Horse *p2 = new Pegasus; //输出：Horse 申请了空间...
	                                           //          Pegasus 申请了空间...         
	
	cout << endl; 
	
	p1->Fly();	//输出：Just a horse.
	p2->Fly();  //输出：I can fly!
	cout << endl; 
	
	delete p1;	//输出：Horse 释放了空间...
	delete p2;  //输出：Pegasus 释放了空间... 
	                  //          Horse 释放了空间... 
	return 0;
}

要求输出：

Horse 申请了空间...
Horse 申请了空间...
Pegasus 申请了空间...

Just a horse.
I can fly!

Horse 释放了空间...
Pegasus 释放了空间...
Horse 释放了空间...

代码实现，IDE为VS2017

#include "stdafx.h"
#include<iostream>
using namespace std;

class Horse {

public:
	Horse(){
		cout << "Horse 申请了空间..." << endl;
	}
	virtual void Fly() {
		cout << "Just a horse." << endl;
	}
	virtual ~Horse() {    //析构函数为虚函数
		cout << "Horse 释放了空间..." << endl;
	}
};

class Pegasus :public Horse {

public:
	Pegasus():Horse(){
		cout << "Pegasus 申请了空间..." << endl;
	}
	void Fly() {
		cout <<"I can fly!"<< endl;
	}
	~Pegasus() {
		cout << "Pegasus 释放了空间..." << endl;
	}
};



int main()
{
	Horse *p1 = new Horse;   //输出：Horse 申请了空间...
	Horse *p2 = new Pegasus; //输出：Horse 申请了空间...
                                 //      Pegasus 申请了空间...
        //先调用基类的构造函数，再调用派生类的构造函数                
	cout << endl;
	p1->Fly();	//输出：Just a horse.
	p2->Fly();  //输出：I can fly!
	cout << endl;

	delete p1;	//输出：Horse 释放了空间...
	delete p2;      //输出：Pegasus 释放了空间... 
		        //      Horse 释放了空间... 
        //先调用派生类的析构函数，再调用基类的析构函数
	system("pause");
	return 0;
}