////   This file contains the C++ code from Program 14.9 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/pgm14_09.cpp//template <class T>unsigned int BinarySearch (    Array<T> const& array, T const& target,    unsigned int i, unsigned int n){    if (n == 0)	throw invalid_argument ("empty array");    if (n == 1)    {	if (array [i] == target)	    return i;	throw domain_error ("target not found");    }    else    {	unsigned int const j = i + n / 2;	if (array [j] <= target)	    return BinarySearch (array, target, j, n - n / 2);	else	    return BinarySearch (array, target, i, n / 2);    }}