Overloading + operator to add fractions

Question

I've spent the last couple of hours trying to find a solution to my problem online, and couldn't. For the record, I am a beginner and probably make loads of mistakes, I would like to ask for a help with one issue: I'm trying to write program, that will add two fractions and show me the results. For example, I have entered "5/11" and "3/11", and I want it to dispay "8/11". However, it gives me "0/1" I've overloaded "+" and ">>" operators, but I'm not sure if I did it correctly. Here's the code:

#include <iostream>
using namespace std;
class fraction
{
public:
int num;
int den;
int sign;
fraction (int top);
fraction (int top, int bot);
};

ostream& operator<< (ostream& z , fraction u) {
if (u.sign==-1)   z<<"-";
  z<<u.num<<"/"<<u.den;
  return z;
}
fraction operator+ (fraction x, fraction y) {
x.num*y.den+y.num*x.den;
return 0; }


fraction::fraction (int top, int bot)
{
den=bot;
num=top;
sign=1;


if (bot<0)
{
sign=-sign;
den=-den;
}

if (top<0)
{
sign=-sign;
num=-num;
}

if (bot==0)
{
num=0;
den=1;
sign=1;
}

}

fraction::fraction (int top)
{
    den=1;
    num=top;
    sign=1;
    if (top<0)
    {
        sign=-sign;
        num=-num;
    }
}

int main() {
fraction x (5,11),y (4,11);
cout<<x<<" "<<y;
cout<<"  x+y= "<<x+y;
return 0;
}

Specifically, I believe the problem lies in two spots:

fraction operator+ (fraction x, fraction y) {
x.num*y.den+y.num*x.den;
return 0; }

And:

int main() {
fraction x (5,11),y (4,11);
cout<<x<<" "<<y;
cout<<"  x+y= "<<x+y;
return 0;
}

I know "return 0" in the overload is wrong, but I have no idea what to replace it with. Any help would be really appreciated!

Answer 1

fraction operator+ (fraction x, fraction y) {
return fraction(x.num*y.den+y.num*x.den,x.den*y.den); }