/*
   file to explain this pointer
*/
#include <iostream>
using namespace std;

struct nd{
	nd():n(0),d(0){}
	nd(int a, int b):n(a), d(b){}
	int n;
	int d;
};

class rat{
public:
	nd *pnd;
	rat():pnd(new nd()){}
	rat(int a, int b):pnd(new nd(a,b)){}
	rat(rat&r){
		pnd = new nd(r.pnd->n,r.pnd->d);
	}
	rat& operator=(rat rhs){
		if(&rhs!=this){
		   cout << "in assignment operator"<<endl;
		   cout << this->pnd->n << " " << this->pnd->d << endl;
		   cout << rhs.pnd->n << " " << rhs.pnd->d << endl;
		   pnd->n = rhs.pnd->n;
		   pnd->d = rhs.pnd->d; 

		}
		return *this;
	}
	~rat(){delete pnd;}
};

void main(){
	rat x(1,2), y(14,77);
	rat p(99,98), q(-4,14);
	y = x = q;
	p = q;
	q = q;
}