28 Algorithms library [algorithms]

28.6 Mutating sequence operations [alg.modifying.operations]

28.6.10 Reverse [alg.reverse]

template<class BidirectionalIterator>
  void reverse(BidirectionalIterator first, BidirectionalIterator last);
template<class ExecutionPolicy, class BidirectionalIterator>
  void reverse(ExecutionPolicy&& exec,
               BidirectionalIterator first, BidirectionalIterator last);

Requires: *first shall be swappable ([swappable.requirements]).

Effects: For each non-negative integer i < (last - first) / 2, applies iter_swap to all pairs of iterators first + i, (last - i) - 1.

Requires: BidirectionalIterator shall satisfy the requirements of ValueSwappable ([swappable.requirements]).

Complexity: Exactly (last - first)/2 swaps.

template<class BidirectionalIterator, class OutputIterator>
  OutputIterator
    reverse_copy(BidirectionalIterator first, BidirectionalIterator last,
                 OutputIterator result);
template<class ExecutionPolicy, class BidirectionalIterator, class ForwardIterator>
  ForwardIterator
    reverse_copy(ExecutionPolicy&& exec,
                 BidirectionalIterator first, BidirectionalIterator last,
                 ForwardIterator result);

Requires: The ranges [first, last) and [result, result + (last - first)) shall not overlap.

Effects: Copies the range [first, last) to the range [result, result + (last - first)) such that for every non-negative integer i < (last - first) the following assignment takes place: *(result + (last - first) - 1 - i) = *(first + i).

Returns: result + (last - first).

Complexity: Exactly last - first assignments.