// FILE ex_complex1.cc

#include <iostream>
#include <cmath>

using namespace std;



/// a complex number
class MyComplex
{
private:
  double real_;  // real part
  double imag_;  // imaginary part
  
public:
  // (default) constructor
  MyComplex (double re=0, double im=0)
  {
    real_ = re;
    imag_ = im;
  }
  
  // accessing the real part
  double real () const
  {
    return real_;
  }
  
  // accessing the imaginary part
  double imag () const
  {
    return imag_;
  }
  
  // setting the real part
  void setReal (double re)
  {
    real_ = re;
  }
  
  // setting the imaginary part
  void setImag (double im)
  {
    imag_ = im;
  }
  
  // print to screen
  void print () const
  {
    cout << real_ << " + (" << imag_ << " i)" << endl;
  }
  
}; // class MyComplex




void addComplex (const MyComplex x, const MyComplex y, MyComplex& z)
{
  z.setReal (x.real() + y.real ());
  z.setImag (x.imag() + y.imag ());
}


void multComplex (MyComplex x, MyComplex y, MyComplex& z)
{
  z.setReal (x.real() * y.real() - x.imag() * y.imag());
  z.setImag (x.real() * y.imag() + x.imag() * y.real());
}



int main ()
{
  MyComplex a(1, 2);  // 1 + 2i
  MyComplex b(2, -3); // 2 - 3i
  MyComplex c;
  MyComplex d;

  cout << "a = ";
  a.print ();

  cout << "b = ";
  b.print ();
  
  addComplex (a, b, c);
  
  cout << "c = a + b = ";
  c.print ();
  
  multComplex (a, b, d);

  cout << "d = a * b = ";
  d.print ();
  
}