VMS Help CXXLSTD, Algorithms, reverse_copy *Conan The Librarian |
Standard C++ Library Copyright 1996, Rogue Wave Software, Inc. NAME reverse_copy - Reverse the order of elements in a collection while copying them to a new collecton. SYNOPSIS #include <algorithm> template <class BidirectionalIterator, class OutputIterator> OutputIterator reverse_copy (BidirectionalIterator first, BidirectionalIterator last, OutputIterator result); DESCRIPTION The reverse_copy algorithm copies the range [first, last) to the range [result, result + (last - first)) such that for any non-negative integer i < (last - first), the following assignment takes place: *(result + (last - first) -i) = *(first + i) reverse_copy returns result + (last - first). The ranges [first, last) and [result, result + (last - first)) must not overlap. COMPLEXITY reverse_copy performs exactly (last - first) assignments. EXAMPLE // // reverse.cpp // #include <algorithm> #include <vector> #include <iostream.h> int main () { // // Initialize a vector with an array of integers. // int arr[10] = { 1,2,3,4,5,6,7,8,9,10 }; vector<int> v(arr+0, arr+10); // // Print out elements in original (sorted) order. // cout << "Elements before reverse: " << endl << " "; copy(v.begin(), v.end(), ostream_iterator<int,char>(cout," ")); cout << endl << endl; // // Reverse the ordering. // reverse(v.begin(), v.end()); // // Print out the reversed elements. // cout << "Elements after reverse: " << endl << " "; copy(v.begin(), v.end(), ostream_iterator<int,char>(cout," ")); cout << endl << endl; cout << "A reverse_copy to cout: " << endl << " "; reverse_copy(v.begin(), v.end(), ostream_iterator<int,char>(cout, " ")); cout << endl; return 0; } Output : Elements before reverse: 1 2 3 4 5 6 7 8 9 10 Elements after reverse: 10 9 8 7 6 5 4 3 2 1 A reverse_copy to cout: 1 2 3 4 5 6 7 8 9 10 WARNING If your compiler does not support default template parameters, then you need to always supply the Allocator template argument. For instance, you will need to write : vector<int, allocator<int> > instead of : vector<int> SEE ALSO reverse STANDARDS CONFORMANCE ANSI X3J16/ISO WG21 Joint C++ Committee
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