Additon of complex numbers using operator overloading in c++

Question

Not able to understand a block of code in below given program. Especially the variable, temp which has return type as the complex(the class name) and when we return the variable, temp where it gets returned to? That is return(temp); in the program.

The Program

#include <iostream>
using namespace std;
class complex
{
public:
    complex();//default constructors
    complex(float real, float imag)//constructor for setting values
    {
        x = real;
        y = imag;
    }
    complex operator +(complex);
    void display(void);
    ~complex();

private:
    float x;
    float y;

};

complex::complex()
{
}
////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////
complex complex::operator+(complex c)
{
    complex temp;
    temp.x = x + c.x;
    temp.y = y + c.y;
    return(temp);
}
/////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////////
void complex::display(void) {
    cout << x << "+j" << y << "/n";

}

complex::~complex()
{
}


int main()
{
    complex C1, C2, C3,C4;
    C1 = complex(1, 3.5);//setting of first number
    C2 = complex(2,2.7);//setting of second number
    C4 = complex(2, 5);

    C3 = C1 + C2+C4;//operator overloading
    cout << "C1 = ";
    C1.display();
    cout << "\n C2 = ";
    C2.display();
    cout << "\n C4 = ";
    C4.display();
    cout << "\n C3 = ";
    C3.display();

    system("pause");

    return 0;


}

Unrelated to your problem, but with [the generally bad `using namespace std;`](https://stackoverflow.com/questions/1452721/why-is-using-namespace-std-considered-bad-practice) then you should consider to *not* name your class the same as [the standard `std::complex` class template](http://en.cppreference.com/w/cpp/numeric/complex). — Some programmer dude, Nov 11 '17 at 05:20
As for your problem, if we look at the usage of the `+` operator, lets say we have (the more simple) `C3 = C1 + C2`, then that's the same as `C3 = C1.operator+(C2)`. Does that help you? — Some programmer dude, Nov 11 '17 at 05:24

Arash · Answer 1 · 2017-11-11T05:35:01.987

0

complex C5;
C5=C1+C2;

means

C5=C1.operator+(C2)

equivalent to

complex temp;
temp.x = x + C2.x; /* x=C1.x*/
temp.y = y + C2.y; /* y=C1.y*/
C5=temp;

edited Nov 11 '17 at 05:35

answered Nov 11 '17 at 05:26

Arash

2,114
11
16

You're missing a quite important part there... Where's `C1`? – Some programmer dude Nov 11 '17 at 05:33
@madhurachanna, in an operator, the host class is the first operand (C1) and the second class is the argument (C2) to the operator. – Arash Nov 11 '17 at 09:56
But i heard we don't need to give C1 because it implicit .. And after executing i got the required answer...... – Nov 11 '17 at 10:05
You don't need to write `C1.operator+(C2)` but `C1+C2` is exactly equivalent to it. – Arash Nov 11 '17 at 10:07

Additon of complex numbers using operator overloading in c++

1 Answers1