# Man Page reverse_copy.3

```
Standard C++ Library
Copyright 1998, Rogue Wave Software, Inc.

```

## NAME

```     reverse_copy

- Reverses the order of  elements  in  a  collection  while
copying them to a new collection.

```

## 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>
using namespace std;
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(),           <br>
ostream_iterator<int,char>(cout, " "));
cout << endl;

return 0;
}

Program 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

```

## WARNINGS

```     If your compiler does not support default  template  parame-
ters,  then you always need to supply the Allocator template
argument. For instance, you need to write:

vector<int, allocator<int> >

vector<int>

If your compiler does not support namespaces,  then  you  do
not need the using declaration for std.

```

```     reverse

```