text: #ifndef __STAR_H_
  #define __STAR_H_
  
  class Star //infetface to sign
  {
    public:
  	virtual void sign_contect(void) = 0;
  	virtual void book_ticket(void) = 0;
  	virtual void singe(void) = 0;
  	virtual void collect_money(void) = 0;
  };
  
  #endif