classes

/* This is testing about book <The C++ Programming Language>
 * 3.2 Classes
 * The central language feature of C++ is the class
*/

#include <iostream>
using namespace std;
 
class complex {
  double re, im;  // representation: two doubles
public:
  complex(double r, double i) :re{r}, im{i} {}   // construct complex from two scalars
  complex(double r) :re{r}, im{0} {}             // construct complex from one scalar
  complex() :re{0}, im{0} {}                     // default complex: {0,0}
 
  double real() const { return re; }
  void real(double d) { re=d; }
  double imag() const { return im; }
  void imag(double d) { im=d; }
 
  complex& operator+=(complex z) { re+=z.re, im+=z.im; return *this; }  // add to re and im
  complex& operator-=(complex z) { re-=z.re, im-=z.im; return *this; }
 
  complex& operator*=(complex);     // defined out-of-class somewhere
  complex& operator/=(complex);     // defined out-of-class somewhere
};
 
int main() {
  // your code goes here
  return 0;
}