C++primer plus第六版课后编程题答案13.4

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Port.cpp

#include <iostream>#include <string>//老规矩，我懒得用char*了using namespace std;class Port{private:string brand;//string style;//不需要style，因为派生出来的就是styleint bottles;public:string br(){return brand;};int bot(){return bottles;};Port(const string br="none",int b=0)//const string st="none"{brand=br;//style=st;bottles=b;}Port(const Port &p){brand=p.brand;//style=p.style;bottles=p.bottles;}//Port(){};//因为派生类无参数的构造函数，所以基类必须有相对应的构造函数//发现不用也是可以的，因为第一个有了默认参数值，也可以算是无参构造函数virtual ~Port(){}Port &operator=(const Port &p){return Port(p);//不能使用类似:Port p;p=p2,这种情况，必须声明的同时赋值}Port &operator+=(int b){bottles=bottles+b;return *this;}Port &operator-=(int b){if(bottles>=b)bottles=bottles-b;elsecout<<"error！no so much brand!"<<endl;return *this;}int BottlesCount()const{return bottles;};virtual void Show()const{cout<<"Brand:"<<brand<<endl;//cout<<"Kind:"<<style<<endl;cout<<"Bottlse："<<bottles<<endl;}friend ostream &operator<<(ostream &os,const Port &p){cout<<p.brand<<" ,"<<p.bottles<<endl;return os;}};class VintagePort:public Port{private:string nickname;int year;public:VintagePort(){Port::Port();nickname="default";year=2999;};VintagePort(const string br,int b,const string nn,int y=2999):Port(br,b){nickname=nn;year=y;};VintagePort(const VintagePort &vp){Port::Port(vp);//这样是否可以？,答案是不可以//brand=vp.br();nickname=vp.nickname;year=vp.year;}~VintagePort(){};VintagePort&operator=(const VintagePort &vp){return VintagePort(vp);}void Show(){Port::Show();cout<<"nickname:"<<nickname<<endl;cout<<"year:"<<year<<endl;}friend ostream &operator<<(ostream &os,const VintagePort &p){os<<(const Port &)p;cout<<p.nickname<<" ,"<<p.year<<endl;return os;}};

main134.cpp

#include <iostream>#include "Port.cpp"using namespace std;void main134(){/*Port p1;Port p1("Gallo",20);Port p2(p1);Port p3;//=p1;//p3=p1;//这时候，p3已经采取了默认初始化值//p1.Show();//cout<<p1;//cout<<p3;/*p2.Show();p2+=10;p2.Show();p2-=15;p2.Show();*/VintagePort vp1;//vp1.Show();VintagePort vp2("Vintage",140,"xxoo",1989);//vp2.Show();cout<<vp2;//VintagePort vp3(vp2);//这样子的话，brand,bottles都是Port初始化默认值VintagePort vp3=vp2;//这里我就不改了，自己改一下吧，最近有点累vp3.Show();cin.get();cin.get();}

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