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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 <iostream> #include "Sales_item.h" using std::cout; using std::endl; int main() { Sales_item item, *p; // three ways to obtain size required to hold an object of type Sales_item sizeof(Sales_item); // size required to hold an object of type Sales_item sizeof item; // size of item's type, e.g., sizeof(Sales_item) sizeof *p; // size of type to which p points, e.g., sizeof(Sales_item) cout << "short: " << sizeof(short) << "\n" << "short[3]: " << sizeof(short[3]) << "\n" << "short*: " << sizeof(short*) << "\n" << "short&: " << sizeof(short&) << endl; cout << endl; // to separate output cout << "Sales_item: " << sizeof(Sales_item) << "\n" << "Sales_item[3]: " << sizeof(Sales_item[3]) << "\n" << "Sales_item*: " << sizeof(Sales_item*) << "\n" << "Sales_item&: " << sizeof(Sales_item&) << endl; // Differentiate use of sizeof array and sizeof on a pointer: // First output statement will print 10; second prints 1 // The first statement divides size of entire array by size of an element // The second divides size of a pointer by the size of an int { int x[10]; int *p = x; cout << sizeof(x)/sizeof(*x) << endl; cout << sizeof(p)/sizeof(*p) << endl; } return 0; }