constexpr counted_iterator(I i, iter_difference_t<I> n);
template<class I2>
requires convertible_to<const I2&, I>
constexpr counted_iterator(const counted_iterator<I2>& x);
template<class I2>
requires assignable_from<I&, const I2&>
constexpr counted_iterator& operator=(const counted_iterator<I2>& x);
constexpr const I& base() const & noexcept;
constexpr I base() &&;
constexpr iter_difference_t<I> count() const noexcept;
constexpr decltype(auto) operator*();
constexpr decltype(auto) operator*() const
requires dereferenceable<const I>;
constexpr auto operator->() const noexcept
requires contiguous_iterator<I>;
constexpr decltype(auto) operator[](iter_difference_t<I> n) const
requires random_access_iterator<I>;
template<common_with<I> I2>
friend constexpr bool operator==(
const counted_iterator& x, const counted_iterator<I2>& y);
friend constexpr bool operator==(
const counted_iterator& x, default_sentinel_t);
template<common_with<I> I2>
friend constexpr strong_ordering operator<=>(
const counted_iterator& x, const counted_iterator<I2>& y);
friend constexpr iter_rvalue_reference_t<I>
iter_move(const counted_iterator& i)
noexcept(noexcept(ranges::iter_move(i.current)))
requires input_iterator<I>;
template<indirectly_swappable<I> I2>
friend constexpr void
iter_swap(const counted_iterator& x, const counted_iterator<I2>& y)
noexcept(noexcept(ranges::iter_swap(x.current, y.current)));