// header file that illustrates the use of friends

class list; 
class cell;

class list      // a list of integers
{
private:
  cell* front;   // points to first cell
public:
  void insert(int x);     // inserts new cell to front of list
  void print();          // prints data in list
  list();
  ~list();                   // destructor : must erase all cells too!
};  // end of class list

class cell      // object representing a list cell
{             
private:
  int head;              // data stored in cell
  cell* tail;            // pointer to next cell/rest of list
public:
  cell(int h, cell* t);              // constructor
  ~cell();                           // destructor

  friend void list::print();         // friendly functions that can access
  friend list::~list();              // the private vars of cell class

};