// demonstration of linked data.   Model of a small public library
// To Be Done:  returning copies of books, removing patrons, editting data on file....
#include <iostream>
#include <string>

using namespace std;


class Person{
public:
	string name;
	string address;
	Person(string n="Unknown", string a="no fixed abode"): name(n), address(a) {}
};
class Patron : public Person{
public:
	Patron * next;
	Patron(string n="Unknown", string a="no fixed abode"): Person(n,a),
		next(NULL){}
};
class Book{
public:
	string ISBN;
	string title;
	Book * next;
	Book(string i="0000000000", string t="unknown title"):ISBN(i), title(t),
		next(NULL){}
};
class Copy{
public:
	Book * book;
	int copy;
	Copy * previous;
	Copy * next;
	Copy(Book *b, Copy * p): book(b), previous(p), next(NULL){
	  if(previous){
		 copy = previous->copy + 1; 
		 previous -> next = this;
		 
	  } else {
		 copy=1;
	  }
	}
};
class Loan{
public:
	Copy *  borrowed;
	Person * patron;
	Loan * next;
	Loan * previous;
	Loan( Loan * pr, Copy * b, Person * p ): borrowed(b), patron(p),
		 next(NULL), previous(pr){
	  if(previous){
		 previous -> next = this;
		 
	  } 
	}
};
int main()
{
	Patron me("Dick", "JBH341");
	Book scansholm("0-201-72168", "C++ from the beginning");
	Copy acopy(&scansholm, NULL);
	Loan aloan(NULL, &acopy, &me);

	cerr << (&aloan)->patron->name << endl;
	cerr << (&aloan)->borrowed->book->title << endl;
}