班上一位同学参加了软考，问我这样一道题目，结果出乎我的意料：

class SalesTicket {
public:
 virtual void printTicket(){cout<<"\n这里是正文"<<endl;}
};

class Decorator:public SalesTicket{
 SalesTicket *ticket;
public:
 Decorator(SalesTicket *t){ticket=t;}
 void printTicket(){
  if(ticket!=NULL){
   ticket->printTicket();}
 }
};

class HeadDecorator:public Decorator{
public:
 HeadDecorator(SalesTicket *t):Decorator(t){}
 void printTicket(){
  cout<<"\n这里是票据的抬头"<<endl;
  Decorator::printTicket();
 }
};

class FootDecorator:public Decorator{
public:
 FootDecorator(SalesTicket *t):Decorator(t){}
 void printTicket(){
  Decorator::printTicket();
  cout<<"\n这里是票据的脚注"<<endl;
 }
};

void main(void)
{
 SalesTicket t;
 FootDecorator f(&t);
    HeadDecorator h(&f);
 h.printTicket();
 cout<<"\n------------------------"<<endl;
 FootDecorator a(NULL);
 HeadDecorator b(&a);
 b.printTicket();

}

有兴趣的可以做一下啊，使你功力倍增

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