///////    Refstr.h    ///////
#include<iostream.h>
#include<string.h>

#define OP operator


class Refstr
{ public:
     Refstr(char *str/* = ""*/);         // constructor
     Refstr(const Refstr& s);        // copy constructor
     Refstr& OP = (const Refstr& s); // assignment
     int cmp(const Refstr& s) const;
     unsigned show_cnt() {   return(ptr->cnt);  }
     void display();
     ~Refstr();
  private:
  // nested class
     class Cell
     { public:
          Cell( char *s );
          char *str;
          unsigned cnt;
          ~Cell() { cout << "~Cell" << endl; delete [] str; }
     };
     Cell *ptr;
};