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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 <vector> using std:: vector; #include <iostream> using std::cout; using std::endl; #include <string> using std::string; // implement strcmp-like generic compare function template <typename T> int compare2(T, T); template <typename T> int compare2(T v1, T v2) { // as before cout << "compare2(T, T)" << endl; if (v1 < v2) return -1; if (v2 < v1) return 1; return 0; } // plain functions to handle C-style character strings int compare2(const char* v1, const char* v2) { cout << "compare2(const char*, const char*)" << endl; return strcmp(v1, v2); } // compares two objects template <typename T> int compare(const T&, const T&); // compares elements in two sequences template <class U, class V> int compare(U, U, V); // plain functions to handle C-style character strings int compare(const char*, const char*); // compares two objects template <typename T> int compare(const T &v1, const T &v2) { cout << "compare(const T&, const T&)" << endl; if (v1 < v2) return -1; if (v2 < v1) return 1; return 0; } // compares elements in two sequences template <class U, class V> int compare(U beg1, U end1, V beg2) { cout << "compare(U, U, V)" << endl; while (beg1 != end1) { if (*beg1 < *beg2) return -1; if (*beg2 < *beg1) return 1; ++beg1; ++beg2; } return 0; // if we got here, the two sequences are equal } // plain functions to handle C-style character strings int compare(const char* v1, const char* v2) { cout << "compare(const char*, const char*)" << endl; return strcmp(v1, v2); } int main() { cout << "calling compare(1, 0);" << endl; // calls compare(const T&, const T&) with T bound to int compare(1, 0); cout << "\ncalling compare(vector iters);" << endl; // calls compare(U, U, V), with U and V bound to vector<int>::iterator vector<int> ivec1(10), ivec2(20); compare(ivec1.begin(), ivec1.end(), ivec2.begin()); int ia1[] = {0,1,2,3,4,5,6,7,8,9}; // calls compare(U, U, V) with U bound to int* // and V bound to vector<int>::iterator compare(ia1, ia1 + 10, ivec1.begin()); cout << "\ncalling compare(const_arr1, const_arr2);" << endl; // calls the ordinary function taking const char* parameters const char const_arr1[] = "world", const_arr2[] = "hi"; compare(const_arr1, const_arr2); cout << "\ncalling compare(s1, s2);" << endl; // calls compare(const T&,const T&) with T bound to string string s1 = "hi", s2 = "world"; compare(s1, s2); cout << "\ncalling compare(ch_arr1, ch_arr2);" << endl; // calls the ordinary function taking const char* parameters char ch_arr1[] = "world", ch_arr2[] = "hi"; compare(ch_arr1, ch_arr2); cout << "\ncalling compare(p1, p2);" << endl; char *p1 = ch_arr1, *p2 = ch_arr2; compare(p1, p2); cout << "\ncalling compare(ch_arr1, const_arr1);" << endl; cout << "calling compare(ch_arr2, const_arr1);" << endl; cout << "calling compare(0, 0);" << endl; compare(ch_arr1, const_arr1); compare(ch_arr2, const_arr2); compare(0, 0); cout << "\ncalling compare2(ch_arr1, ch_arr2);" << endl; cout << "calling compare2(p1, p2);" << endl; cout << "calling compare(const_arr1, const_arr2);" << endl; cout << "calling compare(cp1, cp2);" << endl; // calls compare2(T, T) with T bound to char* compare2(ch_arr1, ch_arr2); // calls compare2(T, T) with T bound to char* compare2(p1, p2); // calls the ordinary function taking const char* parameters compare2(const_arr1, const_arr2); const char *cp1 = const_arr1, *cp2 = const_arr2; // calls the ordinary function taking const char* parameters compare2(cp1, cp2); return 0; }