reverse_copy (3C++std) - Tru64 UNIX
Standard C++ LibraryCopyright 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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