[range.iter.op.next]

template<input_or_output_iterator I>
  constexpr I ranges::next(I x);

Effects: Equivalent to: ++x; return x;

template<input_or_output_iterator I>
  constexpr I ranges::next(I x, iter_difference_t<I> n);

Effects: Equivalent to: ranges::advance(x, n); return x;

template<input_or_output_iterator I, sentinel_for<I> S>
  constexpr I ranges::next(I x, S bound);

Effects: Equivalent to: ranges::advance(x, bound); return x;

template<input_or_output_iterator I, sentinel_for<I> S>
  constexpr I ranges::next(I x, iter_difference_t<I> n, S bound);

Effects: Equivalent to: ranges::advance(x, n, bound); return x;

24 Iterators library [iterators]