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//Download by http://www.NewXing.com /* * This file contains code from "C++ Primer, Fourth Edition", by Stanley B. * Lippman, Jose Lajoie, and Barbara E. Moo, and is covered under the * copyright and warranty notices given in that book: * * "Copyright (c) 2005 by Objectwrite, Inc., Jose Lajoie, and Barbara E. Moo." * * * "The authors and publisher have taken care in the preparation of this book, * but make no expressed or implied warranty of any kind and assume no * responsibility for errors or omissions. No liability is assumed for * incidental or consequential damages in connection with or arising out of the * use of the information or programs contained herein." * * Permission is granted for this code to be used for educational purposes in * association with the book, given proper citation if and when posted or * reproduced.Any commercial use of this code requires the explicit written * permission of the publisher, Addison-Wesley Professional, a division of * Pearson Education, Inc. Send your request for permission, stating clearly * what code you would like to use, and in what specific way, to the following * address: * * Pearson Education, Inc. * Rights and Contracts Department * 75 Arlington Street, Suite 300 * Boston, MA 02216 * Fax: (617) 848-7047 */ #include "MS_Queue.h" #include <stdexcept> using std::out_of_range; #include <iostream> using std::ostream; #include <cstring> using std::strlen; using std::strncpy; void Queue<const char*>::push(const char *const &val) { // allocate a new character array and copy characters from val char* new_item = new char[strlen(val) + 1]; strncpy(new_item, val, strlen(val) + 1); // store pointer to newly allocated and initialized element QueueItem<const char*> *pt = new QueueItem<const char*>(new_item); // put item onto existing queue if (empty()) head = tail = pt; // queue has only one element else { tail->next = pt; // add new element to end of queue tail = pt; } } void Queue<const char*>::pop() { // remember head so we can delete it QueueItem<const char*> *p = head; delete head->item; // delete the array allocated in push head = head->next; // head now points to next element delete p; // delete old head element }