ContainerOut carthesian_product_n(std::size_t power, const ContainerIn& xs_in)
{
if (power == 0)
return ContainerOut(1);
std::vector<T> xs = convert_container<std::vector<T>>(xs_in);
auto idxs = all_idxs(xs);
auto result_idxss = internal::helper_carthesian_product_n_idxs(power, idxs);
typedef typename ContainerOut::value_type ContainerOutInner;
auto to_result_cont = [&](const std::vector<std::size_t>& indices)
{
return convert_container_and_elems<ContainerOutInner>(
elems_at_idxs(indices, xs));
};
return transform(to_result_cont, result_idxss);
}
auto enumerate(const Container& xs)
{
return zip(all_idxs(xs), xs);
}