3. 多态的应用：饮品的制作

#include <iostream>
using namespace std;
class makeDrink{
public:
    virtual void step1() = 0;
    virtual void step2() = 0;
    virtual void step3() = 0;
    virtual void step4() = 0;
    void make(){
        step1();
        step2();
        step3();
        step4();
    }
};
class makeCoffee: public makeDrink{
public:
    void step1(){
        cout << "boil water" << endl;
    }
    void step2(){
        cout << "put in couple" << endl;
    }
    void step3(){
        cout << "boil coffee" << endl;
    }
    void step4(){
        cout << "put some milk" << endl;
    }
};
class makeTea: public makeDrink{
public:
    void step1(){
        cout << "boil water" << endl;
    }
    void step2(){
        cout << "put in couple" << endl;
    }
    void step3(){
        cout << "boil tea" << endl;
    }
    void step4(){
        cout << "put something" << endl;
    }
};
void doWork(makeDrink& domake){
    domake.make();
}
int main(){
    makeTea tea;
    makeCoffee coffee;
    doWork(tea);
    doWork(coffee);
    system("pause");
    return 0;
}