#include 
     
      #include 
      
       using namespace std;class MachinePets{public:    MachinePets(const string s):nickname(s){};    string getNickname() {return nickname;};    virtual string talk()=0;private:    string nickname;    };class PetCats:public MachinePets{    public:        PetCats(const string s):MachinePets(s){};        string talk() {return "miao wu~";}};class PetDogs:public MachinePets{    public:        PetDogs(const string s):MachinePets(s){}        string talk() {return "wang wang~";};};void play(MachinePets *p){    cout<
       
        getNickname()<<"says"<
        
         talk()<