////   This file contains the C++ code from Program 9.13 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/pgm09_13.cpp//NaryTree::NaryTree (unsigned int _degree) :    key (0),    degree (_degree),    subtree (0)    {}NaryTree::NaryTree (unsigned int _degree, Object& _key):    key (&_key),    degree (_degree),    subtree (_degree){    for (unsigned int i = 0; i < degree; ++i)	subtree [i] = new NaryTree (degree);}