用C++编写RationalNumber类

我需要帮助完成一项任务。我对这一切还是个新手。我想去

创建一个具有以下功能的类RatinalNumber（分数）：

创建一个构造函数，该构造函数可以防止分数中的0分母，减少或简化非简化形式的分数，并避免负分母。重载此类的加法、减法、乘法和除法运算符。重载此类的关系运算符和相等运算符。

当我把分数加在一起时，我很难让它们适当地减少。例如，如果我的第一个分数是1/3，第二个分数也是1/3，那么答案应该是2/3。然而，每当我运行程序时，无论我放入什么分数，答案都是2/1。

这是我的RatinalNumber头文件：

#pragma once
#include <iostream>
using namespace std;
//RationalNumber class
class RationalNumber
{
public:
    RationalNumber(); //constructor
    ~RationalNumber(); //destructor
    void retrieveInput();
    int GreatestCommonDenom(int num1, int remainder);
    void reduceFraction(int &num, int &denom);
    void operator+(RationalNumber o1);
    void operator-(RationalNumber o1);
    void operator*(RationalNumber o1);
    //void operator/(RationalNumber o1);
private:
    int num, denom;
};

这是我的RatinalNumber函数：

#include "RationalNumber.h"
#include <iostream>
using namespace std;
//RationalNumber Class Functions
RationalNumber::RationalNumber() //constructor
{
    //initializes objects
    num = 1;
    denom = 1;
}
RationalNumber::~RationalNumber() //destructor
{
    //de-allocates memory
} 
void RationalNumber::retrieveInput() //creates user fractions
{
    int num, denom;
    cout << "nEnter a numerator: nn";
    cin >> num;
    cout << "nEnter a denominator: nn";
    cin >> denom;
    cout << endl;
    //denominator
    while (denom == 0)
    {
        cout << "Please enter a denominator: nn";
        cin >> denom;
    }
    while (denom < 0)
    {
        num *= -1;
        denom *= -1;
    }
    cout << num << "/" << denom << endl;
}
int RationalNumber::GreatestCommonDenom(int num1, int remainder) //gets lowest common denominatior
{
    if (remainder == 0)
    {
        return(num1);
    }
    else
    {
        return(GreatestCommonDenom(remainder, num1%remainder));
    }
}
void RationalNumber::reduceFraction(int &num, int &denom) //reduces the fraction to its lowest form
{
    int reduceFrac = 0;
    if (denom > num)
    {
        reduceFrac = GreatestCommonDenom(denom, num);
    }
    else if (denom < num)
    {
    reduceFrac = GreatestCommonDenom(num, denom);
    }
    else
    {
        reduceFrac = GreatestCommonDenom(num, denom);
    }
    num /= reduceFrac;
    denom /= reduceFrac;
    cout << "After reduction, the answer is " << num << "/" << denom << endl;
}
void RationalNumber::operator+(RationalNumber o1) //adds the fractions
{
    RationalNumber temp;
    temp.num = (this -> num * o1.denom) + (o1.num * this -> denom);
    temp.denom = (this -> denom * o1.denom);
    reduceFraction(temp.num, temp.denom);
}
//void operator-(RationalNumber o1)
//{}
//void operator*(RationalNumber o1)
//{}
//void operator/(RationalNumber o1){}

这是我到目前为止的主要程序：

#include <iostream>
#include "RationalNumber.h"
using namespace std;
int main()
{
    cout << "Welcome!n" << endl;
    cout << "Today we shall preform some math functions on fractions.n" << endl;
    //create two objects
    RationalNumber frac1;
    RationalNumber frac2;
    //retrieve user input for their fractions
    cout << "Enter your first fraction: nn";
    frac1.retrieveInput(); 
    cout << "nEnter your second fraction: nn";
    frac2.retrieveInput();
    //using this to see the output (only temporary)
    frac1.operator+(frac2);
    int answer;
    cout << "Menu" << endl;
    cout << "nWhich would you like to preform on your fractions: n" << endl;
    cout << "1: Additionn" << endl;
    cout << "2: Subtractionn" << endl;
    cout << "3: Multiplicationn" << endl;
    cout << "4: Divisionn" << endl;
    cout << "Enter your option: n" << endl;
    cin >> answer;
    return answer;

    switch (answer)
    {
    case 1:
        frac1.operator+(frac2);
        break;
    default:
        cout << "Invalid option." << endl;
    }
    cout << "n" << endl;
    system("pause");
    return 0;
}

为了输出答案，我在开关方面也遇到了一些问题，但它之后几乎关闭了程序，所以我不知道它在输出什么。非常感谢您的帮助！非常感谢。