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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 <string> using std::string; using std::cout; using std::endl; int main() { string s1("hello, "); string s2("world\n"); string s3 = s1 + s2; // s3 is hello, world\n // print what we've got so far cout << "s1: " << s1 << " s2: " << s2 << " s3: " << s3 << endl; s1 += s2; // equivalent to s1 = s1 + s2 // print after update to s1 cout << "s1: " << s1 << " s2: " << s2 << " s3: " << s3 << endl; { // a better way to ``add'' punctuation string s1("hello"); string s2("world"); string s3 = s1 + ", " + s2 + "\n"; // print again, now there won't be a newline after printing s2 cout << "s1: " << s1 << " s2: " << s2 << " s3: " << s3 << endl; } return 0; }