explicit forward_list(const Allocator&);
explicit forward_list(size_type n, const Allocator& = Allocator());
Effects: Constructs a forward_list object with n default-inserted elements using the specified allocator.
forward_list(size_type n, const T& value, const Allocator& = Allocator());
template <class InputIterator>
forward_list(InputIterator first, InputIterator last, const Allocator& = Allocator());