/// Rational Class definition

using std::ostream;

class Rational {
public:
    Rational(int a, int b): num(a), den(b) {};
    Rational& operator*(Rational&);
    int get_num() const { return num;}
    int get_den() const { return den;}
private:
    int num; ///numerator
    int den; ///denominator
};

ostream& operator<<(ostream& os, const Rational& r){
    return os << r.get_num() << '/' << r.get_den() ;
}

Rational& Rational::operator*(Rational& r2) {
    Rational r3{0,0};
    r3.num = this->num*r2.num;
    r3.den = this->den*r2.den;
    return r3;
}