copy_backward

template<class BidIt1, class BidIt2>
    BidIt2 copy_backward(BidIt1 first, BidIt1 last, BidIt2 x);

The template function evaluates *(x - N - 1) = *(last - N - 1)) once for each N in the range [0, last - first), for strictly decreasing values of N beginning with the highest value. It then returns x - (last - first). If x and first designate regions of storage, x must not be in the range [first, last).