29 Numerics library [numerics]

29.6 Numeric arrays [numarray]

29.6.10 Range access [valarray.range]

The iterator type is a type that meets the requirements of a mutable Cpp17RandomAccessIterator ([random.access.iterators]) and models contiguous_iterator ([iterator.concept.contiguous]).
Its value_type is the template parameter T and its reference type is T&.
The const_iterator type meets the requirements of a constant Cpp17RandomAccessIterator and models contiguous_iterator.
Its value_type is the template parameter T and its reference type is const T&.
The iterators returned by begin and end for an array are guaranteed to be valid until the member function resize(size_t, T) is called for that array or until the lifetime of that array ends, whichever happens first.
iterator begin(); const_iterator begin() const;
Returns: An iterator referencing the first value in the array.
iterator end(); const_iterator end() const;
Returns: An iterator referencing one past the last value in the array.