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Help with overloading functions

MrHatchi87 (59)
hey there, this is my code and I need help figuring why im getting an error:

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//fraction.h 
#include <iostream>
#include <iomanip>
using namespace std;

class fraction
{
private:
 int numerator;
 int denominator;
 int f1;
 int f2;
 int f3;
 int f4;
 int f5;

public:
 fraction() : numerator(), denominator(){}
  //void print();
  fraction add(fraction f2);
  //void read();

  
  friend ostream& operator<< (ostream& out, fraction& f)
  {
   out << f.numerator << "/" << f.denominator;

   return out;
  }

  friend istream& operator >>(istream& in, fraction& f);

  fraction (int n) : numerator (n), denominator (1) {};

  friend ostream& add(fraction& f1, fraction& f2)
  {
   fraction f3 = f1 + f2;
    cout << f3 << "=" << f1 << "+" << f2 << endl;
   fraction f4 = f2 + 2;
    cout << f4 << "=" << f2 << "+" << 2 << endl;
   fraction f5 = 2 + f1;
    cout << f5 << "=" << 2 << "+" << f1 << endl;
  }
 

};


the errors are on 36, 38 and 40. and it says
"no operator "+" matches these operands"
any help is appreciated.
Last edited on
Zhuge (4664)
On those lines you are attempting to use the + operator to add a fraction object to another fraction object but you haven't defined what that + operator would do.
MrHatchi87 (59)
makes a little sense; wonder how i can fix it! Google here i come! :P
Moeljbcp (85)
If you need help finding it, look for overloading operators. The definition will look something like this I believe:
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fraction& operator+(const fraction& rhs) //short for right hand side.
{
    //add them together
    return *this;
}
Zhuge (4664)
Almost. The operator+() should be a const method (it should not modify this; otherwise something like 2+3 would be illegal), and as a result you should create a temporary to hold the sum and return that.
Moeljbcp (85)
Yeah you're correct, my bad. I'm thinking of operator += which does modify this. Thanks for the extra info.
Last edited on
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