////   This file contains the C++ code from Program A.6 of//   "Data Structures and Algorithms//    with Object-Oriented Design Patterns in C++"//   by Bruno R. Preiss.////   Copyright (c) 1998 by Bruno R. Preiss, P.Eng.  All rights reserved.////   http://www.pads.uwaterloo.ca/Bruno.Preiss/books/opus4/programs/pgm0A_06.cpp//void Complex::SetReal (double x)    { real = x; }void Complex::SetImag (double y)    { imag = y; }Complex& Complex::operator = (Complex  const& c){    real = c.real;    imag = c.imag;    return *this;}