As an example of using classes, the program ``complex.C'' in Appendix D illustrates the use of the ``complex<double>'' class. To make sure that you have the C++ compiler working properly, compile and run the program. Note that this program #include's the standard C++ library for complex numbers (so we don't have to program them for ourselves) and, for convenience, makes ``Complex'' a short-hand for ``complex<double>''.
Note that the complex class is used just like any of the familiar variable types int, float, double. The one nice, extra feature is that the standard library includes a handy mechanism for constructing a Complex number whenever we need one (such as 0+2i on the second line of main()).
To practice working with such classes, write a subroutine with the prototype
so that when you uncomment the statement ``z2=cmult(..);'' in ``complex.C'', the program produces the same output as before. In writing this subroutine, you should find that all the familiar rules of working with float and double apply!Complex cmult(Complex a,Complex b);