z#include <iostream.h>

class rational
	{
public:
	rational();
	rational(long n, long d = 1);
	rational &operator+=(rational r);
	rational &operator-=(rational r);
	rational &operator*=(rational r);
	rational &operator/=(rational r);
	rational operator+();
	rational operator-();
	double to_double();
	friend ostream &operator<<(ostream &os, rational
r);
private:
	long num, denom;
	void simplify();
	};

rational operator+(rational r1, rational r2);
rational operator-(rational r1, rational r2)
rational operator*(rational r1, rational r2)
rational operator/(rational r1, rational r2)

rational operator++(rational &r)
rational operator--(rational &r)
rational operator++(rational &r, int);
rational operator--(rational &r, int);


