constexpr const E* begin() const noexcept;
Returns: A pointer to the beginning of the array. If size() == 0 the values of begin() and end() are unspecified but they shall be identical.
constexpr const E* end() const noexcept;
Returns: begin() + size()
constexpr size_t size() const noexcept;
Returns: The number of elements in the array.
Complexity: Constant time.