////   This file contains the C++ code from Program 14.16 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/pgm14_16.cpp//long int RandomNumberGenerator::seed = 1L;long int const RandomNumberGenerator::a = 16807L;long int const RandomNumberGenerator::m = 2147483647L;long int const RandomNumberGenerator::q = 127773L;long int const RandomNumberGenerator::r = 2836L;void RandomNumberGenerator::SetSeed (long int s){    if (s < 1 || s >= m)	throw invalid_argument ("invalid seed");    seed = s;}double RandomNumberGenerator::Next (){    seed = a * (seed % q) - r * (seed / q);    if (seed < 0) 	seed += m;    return (double) seed / (double) m;}