////   This file contains the C++ code from Program 10.16 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/pgm10_16.cpp//unsigned int MWayTree::FindIndex (Object const& object) const{    if (IsEmpty ())	throw domain_error ("invalid operation");    if (object < *key [1])	return 0;    unsigned int left = 1;    unsigned int right = numberOfKeys;    while (left < right)    {	int const middle = (left + right + 1) / 2;	if (object >= *key [middle])	    left = middle;	else	    right = middle - 1U;    }    return left;}Object& MWayTree::Find (Object const& object) const{    if (IsEmpty ())	return NullObject::Instance ();    unsigned int const index = FindIndex (object);    if (index != 0 && object == *key [index])	return *key [index];    else	return subtree [index]->Find (object);}