c++特性之一-----继承

#include <iostream.h>
class Animal
{
public:
        void eat()
        {
                cout<<"animal eat"<<endl;
        }
protected:
        void sleep()
        {
                cout<<"animal sleep"<<endl;
        }
public:
        void breathe()
        {
                cout<<"animal breathe"<<endl;
        }
};

class Fish:public Animal
{
public:

        void test()
        {
                sleep();
        }
  
};

void main()
{
        Animal an;
        Fish fh;
        fh.test();//子类可以通过内部成员函数来访问父类的保护成员
        fh.sleep();//子类不能直接访问父类的保护成员。
}