virtual-call.cpp

#include <iostream>
using namespace std;

class Base
{
    public:
        int Jiao()
        {   
            return JiaoImpl();
        }

    private:
        virtual int JiaoImpl() = 0;
};

class Dog: public Base
{   
    private:
        virtual int JiaoImpl()
        {   
            cout << "Wang" << endl;
        }
};

class Cat: public Base
{   
    private:
        virtual int JiaoImpl()
        {   
            cout << "Miao" << endl;
        }
};

int main()
{   
    Dog dg;
    dg.Jiao();

    Cat ct;
    ct.Jiao();

    Base* a = new Dog();
    a->Jiao();
    Base* b = new Cat();
    b->Jiao();
    return 0;
}