template<class Iterator1, class Iterator2>
constexpr auto operator-(
const reverse_iterator<Iterator1>& x,
const reverse_iterator<Iterator2>& y) -> decltype(y.base() - x.base());
Returns:
y.current - x.current. template<class Iterator>
constexpr reverse_iterator<Iterator> operator+(
typename reverse_iterator<Iterator>::difference_type n,
const reverse_iterator<Iterator>& x);
Returns:
reverse_iterator<Iterator> (x.current - n). template<class Iterator>
constexpr reverse_iterator<Iterator> make_reverse_iterator(Iterator i);
Returns:
reverse_iterator<Iterator>(i).