#include <xmemory>
#include <stdexcept>#define _STD_BEGIN namespace std {
#define _STD_END }_STD_BEGIN// 第一个模板参数
template <class _Val_types>
class _List_val : public _Container_base { };// 第二个模板参数
template <class _Ty, class _Alloc0>
struct _List_base_types { };template <bool _Al_has_storage, class _Alloc_types>
class _List_alloc: public _List_val<typename _Alloc_types::_Val_types> { };template <class _Ty, class _Alloc>  // 这里默认_Alloc不为空类型
class _List_buy     // !is_empty<_Alloc>::value暂不讨论: public _List_alloc<true, _List_base_types<_Ty, _Alloc>> { };template <class _Ty, class _Alloc = allocator<_Ty> >
class list : public _List_buy<_Ty, _Alloc> { };_STD_END

template<class _Ty,class _Alloc0>struct _List_base_types{ // types needed for a container basetypedef _Alloc0 _Alloc;typedef _List_base_types<_Ty, _Alloc> _Myt;typedef _Wrap_alloc<_Alloc> _Alty0;typedef typename _Alty0::template rebind<_Ty>::other _Alty;typedef typename _Get_voidptr<_Alty, typename _Alty::pointer>::type_Voidptr;typedef _List_node<typename _Alty::value_type,_Voidptr> _Node;typedef typename _Alty::template rebind<_Node>::other _Alnod_type;typedef typename _Alnod_type::pointer _Nodeptr;typedef _Nodeptr& _Nodepref;typedef typename _If<_Is_simple_alloc<_Alty>::value,_List_simple_types<typename _Alty::value_type>,_List_iter_types<typename _Alty::value_type,typename _Alty::size_type,typename _Alty::difference_type,typename _Alty::pointer,typename _Alty::const_pointer,typename _Alty::reference,typename _Alty::const_reference,_Nodeptr> >::type_Val_types;};

template<bool,class _Ty1,class _Ty2>struct _If{  // type is _Ty2 for assumed falsetypedef _Ty2 type;};template<class _Ty1,class _Ty2>struct _If<true, _Ty1, _Ty2>{   // type is _Ty1 for assumed truetypedef _Ty1 type;};

template<class _Ty>struct _List_simple_types: public _Simple_types<_Ty>{   // wraps types needed by iteratorstypedef _List_node<_Ty, void *> _Node;typedef _Node *_Nodeptr;};

template<class _Value_type,class _Voidptr>struct _List_node{    // list node_Voidptr _Next; // successor node, or first element if head_Voidptr _Prev;  // predecessor node, or last element if head_Value_type _Myval; // the stored value, unused if headprivate:_List_node& operator=(const _List_node&);};template<class _Value_type>struct _List_node<_Value_type, void *>{   // list nodetypedef _List_node<_Value_type, void *> *_Nodeptr;_Nodeptr _Next; // successor node, or first element if head_Nodeptr _Prev;  // predecessor node, or last element if head_Value_type _Myval; // the stored value, unused if headprivate:_List_node& operator=(const _List_node&);};

        // TEMPLATE CLASS _Simple_types
template<class _Value_type>struct _Simple_types{  // wraps types needed by iteratorstypedef _Value_type value_type;typedef size_t size_type;typedef ptrdiff_t difference_type;typedef value_type *pointer;typedef const value_type *const_pointer;typedef value_type& reference;typedef const value_type& const_reference;};