Rational

#include <iostream>
#include <vector>
#include <map>
#include <set>
#include <sstream>
using namespace std;

int NOD(int a, int b){
    while (a > 0 && b > 0) {
        if (a > b) {
            a %= b;
        } else {
            b %= a;
        }
    }
    return (a+b);
}

class Rational {
public:
    Rational() {
        chisl = 0;
        znam = 1;
    }

    Rational(const int& numerator, const int& denominator) {
        int c;
        int a = numerator;
        int b = denominator;
        bool isA, isB;

        if (a < 0 && b < 0){
            a *= -1;
            b *= -1;
        }
        else if (a < 0 && b > 0){
            a *= -1;
            isA = true;
        }
        else if (a > 0 && b < 0){
            b *= -1;
            isB = true;
        }

        if (a != 0){
            c = NOD(a, b);
            chisl = a / c;
            znam = b / c;
        } else {
            chisl = 0;
            znam = 1;
        }

        if (isA || isB){
            chisl *= -1;
        }
    }

    int Numerator() const {
        return chisl;
    }

    int Denominator() const {
        return znam;
    }

private:
   int chisl;
   int znam;
};

bool operator==(const Rational& lhs, const Rational& rhs){
    if (lhs.Numerator() == rhs.Numerator()
            && lhs.Denominator() == rhs.Denominator()){
        return true;
    } else {
        return false;
    }
}

bool operator!=(const Rational& lhs, const Rational& rhs){
    if (lhs.Numerator() == rhs.Numerator()
            && lhs.Denominator() == rhs.Denominator()){
        return false;
    } else {
        return true;
    }
}

Rational operator+(const Rational& lhs, const Rational& rhs){
    int temp;
    int temp1 = lhs.Denominator();
    if (rhs.Denominator() != lhs.Denominator()){
        temp1 = rhs.Denominator() * lhs.Denominator();
        temp = lhs.Numerator() * rhs.Denominator()
                + rhs.Numerator() * lhs.Denominator();
    } else {
        temp = lhs.Numerator() + rhs.Numerator();
    }
    int c = NOD(temp, temp1);
    return Rational (temp/c, temp1/c);
}

Rational operator-(const Rational& lhs, const Rational& rhs){
    int temp;
    int temp1 = lhs.Denominator();
    if (rhs.Denominator() != lhs.Denominator()){
        temp1 = rhs.Denominator() * lhs.Denominator();
        temp = lhs.Numerator() * rhs.Denominator()
                - rhs.Numerator() * lhs.Denominator();
    } else {
        temp = lhs.Numerator() - rhs.Numerator();
    }
    int c = NOD(temp, temp1);
    return Rational (temp/c, temp1/c);
}

Rational operator*(const Rational& lhs, const Rational& rhs){
    int temp = lhs.Numerator() * rhs.Numerator();
    int temp1 = lhs.Denominator() * rhs.Denominator();
    int c = NOD(temp, temp1);
    return Rational(temp/c, temp1/c);
}

Rational operator/(const Rational& lhs, const Rational& rhs){
    int temp = lhs.Numerator() * rhs.Denominator();
    int temp1 = lhs.Denominator() * rhs.Numerator();
    int c = NOD(temp, temp1);
    return Rational(temp/c, temp1/c);
}

ostream& operator<<(ostream& stream, const Rational& lol){
    stream << lol.Numerator() << "/" << lol.Denominator();
    return stream;
}

istream& operator>>(istream& stream, Rational& lol){
    int a,b;
    if (stream){
        stream >> a;
        stream.ignore(1);
        stream >> b;
        stream.ignore(1);
        lol = Rational(a,b);
    }
    return stream;
}

bool operator<(const Rational& lhs, const Rational& rhs){
    if (lhs.Denominator() == rhs.Denominator()){
        if (lhs.Numerator() < rhs.Numerator()){
            return true;
        } else {
            return false;
        }
    }
    else {
        int a = lhs.Numerator() * rhs.Denominator();
        int b = rhs.Numerator() * lhs.Denominator();
        if (a < b){
            return true;
        } else {
            return false;
        }
    }
}

bool operator>(const Rational& lhs, const Rational& rhs){
    if (lhs.Denominator() == rhs.Denominator()){
        if (lhs.Numerator() < rhs.Numerator()){
            return false;
        } else {
            return true;
        }
    }
    else {
        int a = lhs.Numerator() * rhs.Denominator();
        int b = rhs.Numerator() * lhs.Denominator();
        if (a < b){
            return false;
        } else {
            return true;
        }
    }
}

int main() {
    return 0;
}