reverse_copy


function template
<algorithm>
template <class BidirectionalIterator, class OutputIterator>
  OutputIterator reverse_copy ( BidirectionalIterator first,
                                BidirectionalIterator last, OutputIterator result );

Copy range reversed

Copies the values of the elements in the range [first,last) to the range positions beginning at result, but reversing its order.

The behavior of this function template is equivalent to:
1
2
3
4
5
6
7
 
template <class BidirectionalIterator, class OutputIterator>
  OutputIterator reverse_copy ( BidirectionalIterator first,
                                BidirectionalIterator last, OutputIterator result )
{
  while (first!=last) *result++ = *--last;
  return result;
}


Parameters

first, last
Bidirectional iterators to the initial and final positions of the sequence to be copied reversed. The range used is [first,last), which contains all the elements between first and last, including the element pointed by first but not the element pointed by last.
result
Output iterator to the initial position of the range where the resulting range of values is stored.


Return value

An output iterator pointing to the end of the copied range.

Example

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
 
// reverse_copy example
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

int main () {
  int myints[] ={1,2,3,4,5,6,7,8,9};
  vector<int> myvector;
  vector<int>::iterator it;

  myvector.resize(9);

  reverse_copy (myints, myints+9, myvector.begin());

  // print out content:
  cout << "myvector contains:";
  for (it=myvector.begin(); it!=myvector.end(); ++it)
    cout << " " << *it;

  cout << endl;

  return 0;
}


Output:
myvector contains: 9 8 7 6 5 4 3 2 1


Complexity

Linear: Performs as many assignment operations as the distance between first and last.

See also

reverse Reverse range (function template)
rotate_copy Copy rotated range (function template)
copy Copy range of elements (function template)
copy_backward Copy range of elements backwards (function template)
swap Exchange values of two objects (function template)