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/*
 * 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
*/ 

// swap values of two pointers to int
void ptrswap(int *&v1, int *&v2) 
{
    int *tmp = v2;
    v2 = v1;
    v1 = tmp;
}


#include <iostream>
using std::endl;
using std::cout;

void ptrswap(int *&v1, int *&v2);

int main() 
{
    int i = 10;
    int j = 20;

    int *pi = &i;  // pi points to i
    int *pj = &j;  // pj points to j

    cout << "Before ptrswap():\t*pi: "
         << *pi << "\t*pj: " << *pj << endl;

    ptrswap(pi, pj); // now pi points to j; pj points to i
    cout << "After ptrswap():\t*pi: "
         << *pi << "\t*pj: " << *pj << endl;
    return 0;
}