c++ - 有理赋值运算符

Question

所以在这个项目中，我必须创建一个合理化程序，帮助将数字简化为简化格式。我最挣扎的程序部分是具有长参数的运算符。我正在尝试写出适当的条件，以便 LongRational 将正确存储到 this->_num ， this->_den 但逻辑我写的好像不太对。我的函数参数本身是否有问题，或者无论如何要纠正这个问题。

Rational& Rational::operator += (const Rational& rational)
{
    this->_num += ((rational._num * _den) + (rational._den * _num));
    this->_den += (rational._den * _den);

    return *this;
}

//Part I am having trouble on. Tried editing but unsure if correct.
Rational& Rational::operator += (long LongRational) 
{

    this->_num += (LongRational * _den) + (_num * LongRational);
    this->_den += (LongRational * _num);

    return *this;
}

Rational& Rational::operator -= (const Rational& rational)
{
    this->_num -= ((rational._den * _num) - (_den * rational._num));
    this->_den -= (rational._den * _den);

    return *this;
}

//Part I am having trouble on. Haven't edited this bit yet,
Rational& Rational::operator -= (long LongRational)
{
    this->_num -= LongRational;
    this->_den -= _den;

    return *this;
}

//注意：他希望有一组两个赋值运算符，它们带有参数，将 Rational 对象作为参数，另一个带有 long。