complex number arithmetic

I'm trying to make class "Complex" with operator overload so I can perform c1+c2 etc.
I don't know how to deal with following problem:
I ask user to enter complex number from keyboard and he(she)
type: 2+i3. I can ask to enter Real and Imaginary part separately, but how can I achive this.
I was thinking to enter information from keyboard to string and then parse string like array of character seeking '+' or '-'.
Is it possible to achive this in some other simple way??
Thanks in advance!

>I'm trying to make class "Complex" with operator overload so I can perform c1+c2 etc.
>I ask user to enter complex number from keyboard and he(she)
I hope you aren't trying to ask for this input from within the class. A complex number class doesn't lend itself well to asking for its own input. I would imagine that a good complex class would look something like this:

Code:

---

class Complex {
public:
  Complex ( const int real, const int imaginary );
  Complex ( const Complex& com );
public:
  int real() const;
  int imaginary() const;
public:
  Complex& operator= ( const int rhs );
  Complex& operator+= ( const int rhs );
  Complex& operator-= ( const int rhs );
  Complex& operator*= ( const int rhs );
  Complex& operator/= ( const int rhs );
public:
  Complex& operator= ( const Complex& rhs );
  Complex& operator+= ( const Complex& rhs );
  Complex& operator-= ( const Complex& rhs );
  Complex& operator*= ( const Complex& rhs );
  Complex& operator/= ( const Complex& rhs );
private:
  int real_part;
  int imag_part;
};

---

If, on the other hand, you are parsing input from without and then passing it to your class, parsing a complete string would work, but it really depends on how your program is laid out whether or not there is a better way. I personally would take input in a more simplistic manner to make things easier, such as a complex number pair without an operation that you can work with later:

Code:

---

2 3 4 5 6 7

---

This way you can more easily use formatted input to get what you want:

Code:

---

vector<Complex> get_complex_vector ( string& input )
{
  vector<Complex> ret;
  stringstream sin ( input );
  int re, im;

  while ( sin>> re && sin>> im )
    ret.push_back ( Complex ( re, im ) );

  return ret;
}

---