#include <iostream>

using namespace std;

class Fraction
{
	int nume, deno;
public:
	Fraction()
	{
		nume = 0;
		deno = 1;
	}
	Fraction(int n, int d)
	{
		nume = n;
		deno = d;
	}
	void Set(int n, int d)
        {
                nume = n;
                deno = d;
        }
	void Print() const
	{
		cout << nume << '/' << deno;
	}
	Fraction Mult(Fraction f)
	{
		Fraction t;
		int n, d;
		n = nume*f.nume;
		d = deno*f.deno;
		t.Set(n,d);
		return t;
	}
};	

int main()
{
	Fraction x;
	Fraction y;
	Fraction z;
	int n;
	int d;
	char dummy, op;

	cout << "Input x (n/d or -1/1 to quit): ";
	while (n!=-1 && d!=1)
	{
		cin >> n >> dummy >> d;
		// Set x = n/d?
		x.Set(n,d);
		cout << "Input y (n/d): ";
	       	cin >> n >> dummy >> d;
	        // Set y = n/d?
	        y.Set(n,d);
		cout << "Operation? (+, -, /, *): ";
		cin >> op;
		if (op == '*')
			z = x.Mult(y);
		else
			cout << "I'm working on.";
		// Debug
		cout << "x= ";
		x.Print();
		cout << "\n";
		cout << "y= ";
		y.Print();
		cout << "\n";
		cout << "z= ";
		z.Print();
		cout << "Input x (n/d or -1/1 to quit): ";
		cin >> n >> dummy >> d;
	}
	cout << "\nDone.\n\n";
	return 0;
}