/************************************************************************** * * teller.cpp - Bank teller sample program. * * $Id: teller.cpp 550991 2007-06-26 23:58:07Z sebor $ * *************************************************************************** * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed * with this work for additional information regarding copyright * ownership. The ASF licenses this file to you under the Apache * License, Version 2.0 (the "License"); you may not use this file * except in compliance with the License. You may obtain a copy of * the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or * implied. See the License for the specific language governing * permissions and limitations under the License. * * Copyright 1994-2006 Rogue Wave Software. * **************************************************************************/ #include #include #include #include // A very unsatisfactory, but very portable implementation // of a linear congruential pseudorandom number generator. // (Apologies to D. Lehmer, D. Knuth, R. Sedgewick, et al.) static unsigned long int lcg_seed = 0; inline unsigned long int lcg_rand (int n) { lcg_seed = ((lcg_seed * 11321) + 1) % 32575; return (int) (((double) lcg_seed / 32575.0) * n); } int main () { const int numberOfTellers = 5; const int numberOfMinutes = 60; double totalWait = 0; int numberOfCustomers = 0; std::vector teller (numberOfTellers); std::queue line; for (int t = 0; t < numberOfMinutes; t++) { if (lcg_rand (10) < 9) line.push (Customer (t)); for (int i = 0; i < numberOfTellers; i++) { if (teller[i].isFree () && !line.empty ()) { Customer& frontCustomer = line.front (); numberOfCustomers++; totalWait += t - frontCustomer.arrivalTime; teller[i].addCustomer (frontCustomer); line.pop (); } } } std::cout << "average wait: " << (totalWait / numberOfCustomers) << std::endl; return 0; }