include/__hash_table

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP__HASH_TABLE
#define _LIBCPP__HASH_TABLE

#include <__config>
#include <initializer_list>
#include <memory>
#include <iterator>
#include <algorithm>
#include <cmath>
#include <utility>

#include <__undef_min_max>
#include <__undef___deallocate>

#include <__debug>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif

_LIBCPP_BEGIN_NAMESPACE_STD


#ifndef _LIBCPP_CXX03_LANG
template <class _Key, class _Tp>
union __hash_value_type;
#else
template <class _Key, class _Tp>
struct __hash_value_type;
#endif

#ifndef _LIBCPP_CXX03_LANG
template <class _Tp>
struct __is_hash_value_type_imp : false_type {};

template <class _Key, class _Value>
struct __is_hash_value_type_imp<__hash_value_type<_Key, _Value>> : true_type {};

template <class ..._Args>
struct __is_hash_value_type : false_type {};

template <class _One>
struct __is_hash_value_type<_One> : __is_hash_value_type_imp<typename __uncvref<_One>::type> {};
#endif

_LIBCPP_FUNC_VIS
size_t __next_prime(size_t __n);

template <class _NodePtr>
struct __hash_node_base
{
 typedef __hash_node_base __first_node;

 _NodePtr __next_;

 _LIBCPP_INLINE_VISIBILITY __hash_node_base() _NOEXCEPT : __next_(nullptr) {}
};

template <class _Tp, class _VoidPtr>
struct __hash_node
 : public __hash_node_base
 <
 typename __rebind_pointer<_VoidPtr, __hash_node<_Tp, _VoidPtr> >::type
 >
{
 typedef _Tp __node_value_type;

 size_t __hash_;
 __node_value_type __value_;
};

inline _LIBCPP_INLINE_VISIBILITY
bool
__is_hash_power2(size_t __bc)
{
 return __bc > 2 && !(__bc & (__bc - 1));
}

inline _LIBCPP_INLINE_VISIBILITY
size_t
__constrain_hash(size_t __h, size_t __bc)
{
 return !(__bc & (__bc - 1)) ? __h & (__bc - 1) :
 (__h < __bc ? __h : __h % __bc);
}

inline _LIBCPP_INLINE_VISIBILITY
size_t
__next_hash_pow2(size_t __n)
{
 return size_t(1) << (std::numeric_limits<size_t>::digits - __clz(__n-1));
}


template <class _Tp, class _Hash, class _Equal, class _Alloc> class __hash_table;

template <class _NodePtr> class _LIBCPP_TYPE_VIS_ONLY __hash_iterator;
template <class _ConstNodePtr> class _LIBCPP_TYPE_VIS_ONLY __hash_const_iterator;
template <class _NodePtr> class _LIBCPP_TYPE_VIS_ONLY __hash_local_iterator;
template <class _ConstNodePtr> class _LIBCPP_TYPE_VIS_ONLY __hash_const_local_iterator;
template <class _HashIterator> class _LIBCPP_TYPE_VIS_ONLY __hash_map_iterator;
template <class _HashIterator> class _LIBCPP_TYPE_VIS_ONLY __hash_map_const_iterator;

template <class _Tp>
struct __hash_key_value_types {
 static_assert(!is_reference<_Tp>::value && !is_const<_Tp>::value, "");
 typedef _Tp key_type;
 typedef _Tp __node_value_type;
 typedef _Tp __container_value_type;
 static const bool __is_map = false;

 _LIBCPP_INLINE_VISIBILITY
 static key_type const& __get_key(_Tp const& __v) {
 return __v;
 }
 _LIBCPP_INLINE_VISIBILITY
 static __container_value_type const& __get_value(__node_value_type const& __v) {
 return __v;
 }
 _LIBCPP_INLINE_VISIBILITY
 static __container_value_type* __get_ptr(__node_value_type& __n) {
 return _VSTD::addressof(__n);
 }
#ifndef _LIBCPP_CXX03_LANG
 _LIBCPP_INLINE_VISIBILITY
 static __container_value_type&& __move(__node_value_type& __v) {
 return _VSTD::move(__v);
 }
#endif
};

template <class _Key, class _Tp>
struct __hash_key_value_types<__hash_value_type<_Key, _Tp> > {
 typedef _Key key_type;
 typedef _Tp mapped_type;
 typedef __hash_value_type<_Key, _Tp> __node_value_type;
 typedef pair<const _Key, _Tp> __container_value_type;
 typedef pair<_Key, _Tp> __nc_value_type;
 typedef __container_value_type __map_value_type;
 static const bool __is_map = true;

 _LIBCPP_INLINE_VISIBILITY
 static key_type const& __get_key(__container_value_type const& __v) {
 return __v.first;
 }

 template <class _Up>
 _LIBCPP_INLINE_VISIBILITY
 static typename enable_if<__is_same_uncvref<_Up, __node_value_type>::value,
 __container_value_type const&>::type
 __get_value(_Up& __t) {
 return __t.__cc;
 }

 template <class _Up>
 _LIBCPP_INLINE_VISIBILITY
 static typename enable_if<__is_same_uncvref<_Up, __container_value_type>::value,
 __container_value_type const&>::type
 __get_value(_Up& __t) {
 return __t;
 }

 _LIBCPP_INLINE_VISIBILITY
 static __container_value_type* __get_ptr(__node_value_type& __n) {
 return _VSTD::addressof(__n.__cc);
 }
#ifndef _LIBCPP_CXX03_LANG
 _LIBCPP_INLINE_VISIBILITY
 static __nc_value_type&& __move(__node_value_type& __v) {
 return _VSTD::move(__v.__nc);
 }
#endif

};

template <class _Tp, class _AllocPtr, class _KVTypes = __hash_key_value_types<_Tp>,
 bool = _KVTypes::__is_map>
struct __hash_map_pointer_types {};

template <class _Tp, class _AllocPtr, class _KVTypes>
struct __hash_map_pointer_types<_Tp, _AllocPtr, _KVTypes, true> {
 typedef typename _KVTypes::__map_value_type _Mv;
 typedef typename __rebind_pointer<_AllocPtr, _Mv>::type
 __map_value_type_pointer;
 typedef typename __rebind_pointer<_AllocPtr, const _Mv>::type
 __const_map_value_type_pointer;
};

template <class _NodePtr, class _NodeT = typename pointer_traits<_NodePtr>::element_type>
struct __hash_node_types;

template <class _NodePtr, class _Tp, class _VoidPtr>
struct __hash_node_types<_NodePtr, __hash_node<_Tp, _VoidPtr> >
 : public __hash_key_value_types<_Tp>, __hash_map_pointer_types<_Tp, _VoidPtr>

{
 typedef __hash_key_value_types<_Tp> __base;

public:
 typedef ptrdiff_t difference_type;
 typedef size_t size_type;

 typedef typename __rebind_pointer<_NodePtr, void>::type __void_pointer;

 typedef typename pointer_traits<_NodePtr>::element_type __node_type;
 typedef _NodePtr __node_pointer;

 typedef __hash_node_base<__node_pointer> __node_base_type;
 typedef typename __rebind_pointer<_NodePtr, __node_base_type>::type
 __node_base_pointer;

 typedef _Tp __node_value_type;
 typedef typename __rebind_pointer<_VoidPtr, __node_value_type>::type
 __node_value_type_pointer;
 typedef typename __rebind_pointer<_VoidPtr, const __node_value_type>::type
 __const_node_value_type_pointer;
private:
 static_assert(!is_const<__node_type>::value,
 "_NodePtr should never be a pointer to const");
 static_assert((is_same<typename pointer_traits<_VoidPtr>::element_type, void>::value),
 "_VoidPtr does not point to unqualified void type");
 static_assert((is_same<typename __rebind_pointer<_VoidPtr, __node_type>::type,
 _NodePtr>::value), "_VoidPtr does not rebind to _NodePtr.");
};



template <class _HashIterator>
struct __hash_node_types_from_iterator;
template <class _NodePtr>
struct __hash_node_types_from_iterator<__hash_iterator<_NodePtr> > : __hash_node_types<_NodePtr> {};
template <class _NodePtr>
struct __hash_node_types_from_iterator<__hash_const_iterator<_NodePtr> > : __hash_node_types<_NodePtr> {};
template <class _NodePtr>
struct __hash_node_types_from_iterator<__hash_local_iterator<_NodePtr> > : __hash_node_types<_NodePtr> {};
template <class _NodePtr>
struct __hash_node_types_from_iterator<__hash_const_local_iterator<_NodePtr> > : __hash_node_types<_NodePtr> {};


template <class _NodeValueTp, class _VoidPtr>
struct __make_hash_node_types {
 typedef __hash_node<_NodeValueTp, _VoidPtr> _NodeTp;
 typedef typename __rebind_pointer<_VoidPtr, _NodeTp>::type _NodePtr;
 typedef __hash_node_types<_NodePtr> type;
};

template <class _NodePtr>
class _LIBCPP_TYPE_VIS_ONLY __hash_iterator
{
 typedef __hash_node_types<_NodePtr> _NodeTypes;
 typedef _NodePtr __node_pointer;

 __node_pointer __node_;

public:
 typedef forward_iterator_tag iterator_category;
 typedef typename _NodeTypes::__node_value_type value_type;
 typedef typename _NodeTypes::difference_type difference_type;
 typedef value_type& reference;
 typedef typename _NodeTypes::__node_value_type_pointer pointer;

 _LIBCPP_INLINE_VISIBILITY __hash_iterator() _NOEXCEPT
#if _LIBCPP_STD_VER > 11
 : __node_(nullptr)
#endif
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 __get_db()->__insert_i(this);
#endif
 }

#if _LIBCPP_DEBUG_LEVEL >= 2

 _LIBCPP_INLINE_VISIBILITY
 __hash_iterator(const __hash_iterator& __i)
 : __node_(__i.__node_)
 {
 __get_db()->__iterator_copy(this, &__i);
 }

 _LIBCPP_INLINE_VISIBILITY
 ~__hash_iterator()
 {
 __get_db()->__erase_i(this);
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_iterator& operator=(const __hash_iterator& __i)
 {
 if (this != &__i)
 {
 __get_db()->__iterator_copy(this, &__i);
 __node_ = __i.__node_;
 }
 return *this;
 }

#endif // _LIBCPP_DEBUG_LEVEL >= 2

 _LIBCPP_INLINE_VISIBILITY
 reference operator*() const
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to dereference a non-dereferenceable unordered container iterator");
#endif
 return __node_->__value_;
 }
 _LIBCPP_INLINE_VISIBILITY
 pointer operator->() const
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to dereference a non-dereferenceable unordered container iterator");
#endif
 return pointer_traits<pointer>::pointer_to(__node_->__value_);
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_iterator& operator++()
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to increment non-incrementable unordered container iterator");
#endif
 __node_ = __node_->__next_;
 return *this;
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_iterator operator++(int)
 {
 __hash_iterator __t(*this);
 ++(*this);
 return __t;
 }

 friend _LIBCPP_INLINE_VISIBILITY
 bool operator==(const __hash_iterator& __x, const __hash_iterator& __y)
 {
 return __x.__node_ == __y.__node_;
 }
 friend _LIBCPP_INLINE_VISIBILITY
 bool operator!=(const __hash_iterator& __x, const __hash_iterator& __y)
 {return !(__x == __y);}

private:
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_INLINE_VISIBILITY
 __hash_iterator(__node_pointer __node, const void* __c) _NOEXCEPT
 : __node_(__node)
 {
 __get_db()->__insert_ic(this, __c);
 }
#else
 _LIBCPP_INLINE_VISIBILITY
 __hash_iterator(__node_pointer __node) _NOEXCEPT
 : __node_(__node)
 {}
#endif

 template <class, class, class, class> friend class __hash_table;
 template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_const_iterator;
 template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_iterator;
 template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_map;
 template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_multimap;
};

template <class _NodePtr>
class _LIBCPP_TYPE_VIS_ONLY __hash_const_iterator
{
 static_assert(!is_const<typename pointer_traits<_NodePtr>::element_type>::value, "");
 typedef __hash_node_types<_NodePtr> _NodeTypes;
 typedef _NodePtr __node_pointer;

 __node_pointer __node_;

public:
 typedef __hash_iterator<_NodePtr> __non_const_iterator;

 typedef forward_iterator_tag iterator_category;
 typedef typename _NodeTypes::__node_value_type value_type;
 typedef typename _NodeTypes::difference_type difference_type;
 typedef const value_type& reference;
 typedef typename _NodeTypes::__const_node_value_type_pointer pointer;


 _LIBCPP_INLINE_VISIBILITY __hash_const_iterator() _NOEXCEPT
#if _LIBCPP_STD_VER > 11
 : __node_(nullptr)
#endif
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 __get_db()->__insert_i(this);
#endif
 }
 _LIBCPP_INLINE_VISIBILITY 
 __hash_const_iterator(const __non_const_iterator& __x) _NOEXCEPT
 : __node_(__x.__node_)
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 __get_db()->__iterator_copy(this, &__x);
#endif
 }

#if _LIBCPP_DEBUG_LEVEL >= 2

 _LIBCPP_INLINE_VISIBILITY
 __hash_const_iterator(const __hash_const_iterator& __i)
 : __node_(__i.__node_)
 {
 __get_db()->__iterator_copy(this, &__i);
 }

 _LIBCPP_INLINE_VISIBILITY
 ~__hash_const_iterator()
 {
 __get_db()->__erase_i(this);
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_const_iterator& operator=(const __hash_const_iterator& __i)
 {
 if (this != &__i)
 {
 __get_db()->__iterator_copy(this, &__i);
 __node_ = __i.__node_;
 }
 return *this;
 }

#endif // _LIBCPP_DEBUG_LEVEL >= 2

 _LIBCPP_INLINE_VISIBILITY
 reference operator*() const
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to dereference a non-dereferenceable unordered container const_iterator");
#endif
 return __node_->__value_;
 }
 _LIBCPP_INLINE_VISIBILITY
 pointer operator->() const
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to dereference a non-dereferenceable unordered container const_iterator");
#endif
 return pointer_traits<pointer>::pointer_to(__node_->__value_);
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_const_iterator& operator++()
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to increment non-incrementable unordered container const_iterator");
#endif
 __node_ = __node_->__next_;
 return *this;
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_const_iterator operator++(int)
 {
 __hash_const_iterator __t(*this);
 ++(*this);
 return __t;
 }

 friend _LIBCPP_INLINE_VISIBILITY
 bool operator==(const __hash_const_iterator& __x, const __hash_const_iterator& __y)
 {
 return __x.__node_ == __y.__node_;
 }
 friend _LIBCPP_INLINE_VISIBILITY
 bool operator!=(const __hash_const_iterator& __x, const __hash_const_iterator& __y)
 {return !(__x == __y);}

private:
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_INLINE_VISIBILITY
 __hash_const_iterator(__node_pointer __node, const void* __c) _NOEXCEPT
 : __node_(__node)
 {
 __get_db()->__insert_ic(this, __c);
 }
#else
 _LIBCPP_INLINE_VISIBILITY
 __hash_const_iterator(__node_pointer __node) _NOEXCEPT
 : __node_(__node)
 {}
#endif

 template <class, class, class, class> friend class __hash_table;
 template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_const_iterator;
 template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_map;
 template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_multimap;
};

template <class _NodePtr>
class _LIBCPP_TYPE_VIS_ONLY __hash_local_iterator
{
 typedef __hash_node_types<_NodePtr> _NodeTypes;
 typedef _NodePtr __node_pointer;

 __node_pointer __node_;
 size_t __bucket_;
 size_t __bucket_count_;

public:
 typedef forward_iterator_tag iterator_category;
 typedef typename _NodeTypes::__node_value_type value_type;
 typedef typename _NodeTypes::difference_type difference_type;
 typedef value_type& reference;
 typedef typename _NodeTypes::__node_value_type_pointer pointer;

 _LIBCPP_INLINE_VISIBILITY __hash_local_iterator() _NOEXCEPT
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 __get_db()->__insert_i(this);
#endif
 }

#if _LIBCPP_DEBUG_LEVEL >= 2

 _LIBCPP_INLINE_VISIBILITY
 __hash_local_iterator(const __hash_local_iterator& __i)
 : __node_(__i.__node_),
 __bucket_(__i.__bucket_),
 __bucket_count_(__i.__bucket_count_)
 {
 __get_db()->__iterator_copy(this, &__i);
 }

 _LIBCPP_INLINE_VISIBILITY
 ~__hash_local_iterator()
 {
 __get_db()->__erase_i(this);
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_local_iterator& operator=(const __hash_local_iterator& __i)
 {
 if (this != &__i)
 {
 __get_db()->__iterator_copy(this, &__i);
 __node_ = __i.__node_;
 __bucket_ = __i.__bucket_;
 __bucket_count_ = __i.__bucket_count_;
 }
 return *this;
 }

#endif // _LIBCPP_DEBUG_LEVEL >= 2

 _LIBCPP_INLINE_VISIBILITY
 reference operator*() const
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to dereference a non-dereferenceable unordered container local_iterator");
#endif
 return __node_->__value_;
 }
 _LIBCPP_INLINE_VISIBILITY
 pointer operator->() const
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to dereference a non-dereferenceable unordered container local_iterator");
#endif
 return pointer_traits<pointer>::pointer_to(__node_->__value_);
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_local_iterator& operator++()
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to increment non-incrementable unordered container local_iterator");
#endif
 __node_ = __node_->__next_;
 if (__node_ != nullptr && __constrain_hash(__node_->__hash_, __bucket_count_) != __bucket_)
 __node_ = nullptr;
 return *this;
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_local_iterator operator++(int)
 {
 __hash_local_iterator __t(*this);
 ++(*this);
 return __t;
 }

 friend _LIBCPP_INLINE_VISIBILITY
 bool operator==(const __hash_local_iterator& __x, const __hash_local_iterator& __y)
 {
 return __x.__node_ == __y.__node_;
 }
 friend _LIBCPP_INLINE_VISIBILITY
 bool operator!=(const __hash_local_iterator& __x, const __hash_local_iterator& __y)
 {return !(__x == __y);}

private:
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_INLINE_VISIBILITY
 __hash_local_iterator(__node_pointer __node, size_t __bucket,
 size_t __bucket_count, const void* __c) _NOEXCEPT
 : __node_(__node),
 __bucket_(__bucket),
 __bucket_count_(__bucket_count)
 {
 __get_db()->__insert_ic(this, __c);
 if (__node_ != nullptr)
 __node_ = __node_->__next_;
 }
#else
 _LIBCPP_INLINE_VISIBILITY
 __hash_local_iterator(__node_pointer __node, size_t __bucket,
 size_t __bucket_count) _NOEXCEPT
 : __node_(__node),
 __bucket_(__bucket),
 __bucket_count_(__bucket_count)
 {
 if (__node_ != nullptr)
 __node_ = __node_->__next_;
 }
#endif
 template <class, class, class, class> friend class __hash_table;
 template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_const_local_iterator;
 template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_iterator;
};

template <class _ConstNodePtr>
class _LIBCPP_TYPE_VIS_ONLY __hash_const_local_iterator
{
 typedef __hash_node_types<_ConstNodePtr> _NodeTypes;
 typedef _ConstNodePtr __node_pointer;

 __node_pointer __node_;
 size_t __bucket_;
 size_t __bucket_count_;

 typedef pointer_traits<__node_pointer> __pointer_traits;
 typedef typename __pointer_traits::element_type __node;
 typedef typename remove_const<__node>::type __non_const_node;
 typedef typename __rebind_pointer<__node_pointer, __non_const_node>::type
 __non_const_node_pointer;
public:
 typedef __hash_local_iterator<__non_const_node_pointer>
 __non_const_iterator;

 typedef forward_iterator_tag iterator_category;
 typedef typename _NodeTypes::__node_value_type value_type;
 typedef typename _NodeTypes::difference_type difference_type;
 typedef const value_type& reference;
 typedef typename _NodeTypes::__const_node_value_type_pointer pointer;


 _LIBCPP_INLINE_VISIBILITY __hash_const_local_iterator() _NOEXCEPT
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 __get_db()->__insert_i(this);
#endif
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_const_local_iterator(const __non_const_iterator& __x) _NOEXCEPT
 : __node_(__x.__node_),
 __bucket_(__x.__bucket_),
 __bucket_count_(__x.__bucket_count_)
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 __get_db()->__iterator_copy(this, &__x);
#endif
 }

#if _LIBCPP_DEBUG_LEVEL >= 2

 _LIBCPP_INLINE_VISIBILITY
 __hash_const_local_iterator(const __hash_const_local_iterator& __i)
 : __node_(__i.__node_),
 __bucket_(__i.__bucket_),
 __bucket_count_(__i.__bucket_count_)
 {
 __get_db()->__iterator_copy(this, &__i);
 }

 _LIBCPP_INLINE_VISIBILITY
 ~__hash_const_local_iterator()
 {
 __get_db()->__erase_i(this);
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_const_local_iterator& operator=(const __hash_const_local_iterator& __i)
 {
 if (this != &__i)
 {
 __get_db()->__iterator_copy(this, &__i);
 __node_ = __i.__node_;
 __bucket_ = __i.__bucket_;
 __bucket_count_ = __i.__bucket_count_;
 }
 return *this;
 }

#endif // _LIBCPP_DEBUG_LEVEL >= 2

 _LIBCPP_INLINE_VISIBILITY
 reference operator*() const
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to dereference a non-dereferenceable unordered container const_local_iterator");
#endif
 return __node_->__value_;
 }
 _LIBCPP_INLINE_VISIBILITY
 pointer operator->() const
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to dereference a non-dereferenceable unordered container const_local_iterator");
#endif
 return pointer_traits<pointer>::pointer_to(__node_->__value_);
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_const_local_iterator& operator++()
 {
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
 "Attempted to increment non-incrementable unordered container const_local_iterator");
#endif
 __node_ = __node_->__next_;
 if (__node_ != nullptr && __constrain_hash(__node_->__hash_, __bucket_count_) != __bucket_)
 __node_ = nullptr;
 return *this;
 }

 _LIBCPP_INLINE_VISIBILITY
 __hash_const_local_iterator operator++(int)
 {
 __hash_const_local_iterator __t(*this);
 ++(*this);
 return __t;
 }

 friend _LIBCPP_INLINE_VISIBILITY
 bool operator==(const __hash_const_local_iterator& __x, const __hash_const_local_iterator& __y)
 {
 return __x.__node_ == __y.__node_;
 }
 friend _LIBCPP_INLINE_VISIBILITY
 bool operator!=(const __hash_const_local_iterator& __x, const __hash_const_local_iterator& __y)
 {return !(__x == __y);}

private:
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_INLINE_VISIBILITY
 __hash_const_local_iterator(__node_pointer __node, size_t __bucket,
 size_t __bucket_count, const void* __c) _NOEXCEPT
 : __node_(__node),
 __bucket_(__bucket),
 __bucket_count_(__bucket_count)
 {
 __get_db()->__insert_ic(this, __c);
 if (__node_ != nullptr)
 __node_ = __node_->__next_;
 }
#else
 _LIBCPP_INLINE_VISIBILITY
 __hash_const_local_iterator(__node_pointer __node, size_t __bucket,
 size_t __bucket_count) _NOEXCEPT
 : __node_(__node),
 __bucket_(__bucket),
 __bucket_count_(__bucket_count)
 {
 if (__node_ != nullptr)
 __node_ = __node_->__next_;
 }
#endif
 template <class, class, class, class> friend class __hash_table;
 template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_const_iterator;
};

template <class _Alloc>
class __bucket_list_deallocator
{
 typedef _Alloc allocator_type;
 typedef allocator_traits<allocator_type> __alloc_traits;
 typedef typename __alloc_traits::size_type size_type;

 __compressed_pair<size_type, allocator_type> __data_;
public:
 typedef typename __alloc_traits::pointer pointer;

 _LIBCPP_INLINE_VISIBILITY
 __bucket_list_deallocator()
 _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
 : __data_(0) {}

 _LIBCPP_INLINE_VISIBILITY
 __bucket_list_deallocator(const allocator_type& __a, size_type __size)
 _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
 : __data_(__size, __a) {}

#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES

 _LIBCPP_INLINE_VISIBILITY
 __bucket_list_deallocator(__bucket_list_deallocator&& __x)
 _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
 : __data_(_VSTD::move(__x.__data_))
 {
 __x.size() = 0;
 }

#endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES

 _LIBCPP_INLINE_VISIBILITY
 size_type& size() _NOEXCEPT {return __data_.first();}
 _LIBCPP_INLINE_VISIBILITY
 size_type size() const _NOEXCEPT {return __data_.first();}

 _LIBCPP_INLINE_VISIBILITY
 allocator_type& __alloc() _NOEXCEPT {return __data_.second();}
 _LIBCPP_INLINE_VISIBILITY
 const allocator_type& __alloc() const _NOEXCEPT {return __data_.second();}

 _LIBCPP_INLINE_VISIBILITY
 void operator()(pointer __p) _NOEXCEPT
 {
 __alloc_traits::deallocate(__alloc(), __p, size());
 }
};

template <class _Alloc> class __hash_map_node_destructor;

template <class _Alloc>
class __hash_node_destructor
{
 typedef _Alloc allocator_type;
 typedef allocator_traits<allocator_type> __alloc_traits;

public:
 typedef typename __alloc_traits::pointer pointer;
private:
 typedef __hash_node_types<pointer> _NodeTypes;

 allocator_type& __na_;

 __hash_node_destructor& operator=(const __hash_node_destructor&);

public:
 bool __value_constructed;

 _LIBCPP_INLINE_VISIBILITY
 explicit __hash_node_destructor(allocator_type& __na,
 bool __constructed = false) _NOEXCEPT
 : __na_(__na),
 __value_constructed(__constructed)
 {}

 _LIBCPP_INLINE_VISIBILITY
 void operator()(pointer __p) _NOEXCEPT
 {
 if (__value_constructed)
 __alloc_traits::destroy(__na_, _NodeTypes::__get_ptr(__p->__value_));
 if (__p)
 __alloc_traits::deallocate(__na_, __p, 1);
 }

 template <class> friend class __hash_map_node_destructor;
};

template <class _Tp, class _Hash, class _Equal, class _Alloc>
class __hash_table
{
public:
 typedef _Tp value_type;
 typedef _Hash hasher;
 typedef _Equal key_equal;
 typedef _Alloc allocator_type;

private:
 typedef allocator_traits<allocator_type> __alloc_traits;
 typedef typename
 __make_hash_node_types<value_type, typename __alloc_traits::void_pointer>::type
 _NodeTypes;
public:

 typedef typename _NodeTypes::__node_value_type __node_value_type;
 typedef typename _NodeTypes::__container_value_type __container_value_type;
 typedef typename _NodeTypes::key_type key_type;
 typedef value_type& reference;
 typedef const value_type& const_reference;
 typedef typename __alloc_traits::pointer pointer;
 typedef typename __alloc_traits::const_pointer const_pointer;
#ifndef _LIBCPP_ABI_FIX_UNORDERED_CONTAINER_SIZE_TYPE
 typedef typename __alloc_traits::size_type size_type;
#else
 typedef typename _NodeTypes::size_type size_type;
#endif
 typedef typename _NodeTypes::difference_type difference_type;
public:
 // Create __node

 typedef typename _NodeTypes::__node_type __node;
 typedef typename __rebind_alloc_helper<__alloc_traits, __node>::type __node_allocator;
 typedef allocator_traits<__node_allocator> __node_traits;
 typedef typename _NodeTypes::__void_pointer __void_pointer;
 typedef typename _NodeTypes::__node_pointer __node_pointer;
 typedef typename _NodeTypes::__node_pointer __node_const_pointer;
 typedef typename _NodeTypes::__node_base_type __first_node;
 typedef typename _NodeTypes::__node_base_pointer __node_base_pointer;

private:
 // check for sane allocator pointer rebinding semantics. Rebinding the
 // allocator for a new pointer type should be exactly the same as rebinding
 // the pointer using 'pointer_traits'.
 static_assert((is_same<__node_pointer, typename __node_traits::pointer>::value),
 "Allocator does not rebind pointers in a sane manner.");
 typedef typename __rebind_alloc_helper<__node_traits, __first_node>::type
 __node_base_allocator;
 typedef allocator_traits<__node_base_allocator> __node_base_traits;
 static_assert((is_same<__node_base_pointer, typename __node_base_traits::pointer>::value),
 "Allocator does not rebind pointers in a sane manner.");

private:

 typedef typename __rebind_alloc_helper<__node_traits, __node_pointer>::type __pointer_allocator;
 typedef __bucket_list_deallocator<__pointer_allocator> __bucket_list_deleter;
 typedef unique_ptr<__node_pointer[], __bucket_list_deleter> __bucket_list;
 typedef allocator_traits<__pointer_allocator> __pointer_alloc_traits;
 typedef typename __bucket_list_deleter::pointer __node_pointer_pointer;

 // --- Member data begin ---
 __bucket_list __bucket_list_;
 __compressed_pair<__first_node, __node_allocator> __p1_;
 __compressed_pair<size_type, hasher> __p2_;
 __compressed_pair<float, key_equal> __p3_;
 // --- Member data end ---

 _LIBCPP_INLINE_VISIBILITY
 size_type& size() _NOEXCEPT {return __p2_.first();}
public:
 _LIBCPP_INLINE_VISIBILITY
 size_type size() const _NOEXCEPT {return __p2_.first();}

 _LIBCPP_INLINE_VISIBILITY
 hasher& hash_function() _NOEXCEPT {return __p2_.second();}
 _LIBCPP_INLINE_VISIBILITY
 const hasher& hash_function() const _NOEXCEPT {return __p2_.second();}

 _LIBCPP_INLINE_VISIBILITY
 float& max_load_factor() _NOEXCEPT {return __p3_.first();}
 _LIBCPP_INLINE_VISIBILITY
 float max_load_factor() const _NOEXCEPT {return __p3_.first();}

 _LIBCPP_INLINE_VISIBILITY
 key_equal& key_eq() _NOEXCEPT {return __p3_.second();}
 _LIBCPP_INLINE_VISIBILITY
 const key_equal& key_eq() const _NOEXCEPT {return __p3_.second();}

 _LIBCPP_INLINE_VISIBILITY
 __node_allocator& __node_alloc() _NOEXCEPT {return __p1_.second();}
 _LIBCPP_INLINE_VISIBILITY
 const __node_allocator& __node_alloc() const _NOEXCEPT
 {return __p1_.second();}

public:
 typedef __hash_iterator<__node_pointer> iterator;
 typedef __hash_const_iterator<__node_pointer> const_iterator;
 typedef __hash_local_iterator<__node_pointer> local_iterator;
 typedef __hash_const_local_iterator<__node_pointer> const_local_iterator;

 _LIBCPP_INLINE_VISIBILITY
 __hash_table()
 _NOEXCEPT_(
 is_nothrow_default_constructible<__bucket_list>::value &&
 is_nothrow_default_constructible<__first_node>::value &&
 is_nothrow_default_constructible<__node_allocator>::value &&
 is_nothrow_default_constructible<hasher>::value &&
 is_nothrow_default_constructible<key_equal>::value);
 _LIBCPP_INLINE_VISIBILITY
 __hash_table(const hasher& __hf, const key_equal& __eql);
 __hash_table(const hasher& __hf, const key_equal& __eql,
 const allocator_type& __a);
 explicit __hash_table(const allocator_type& __a);
 __hash_table(const __hash_table& __u);
 __hash_table(const __hash_table& __u, const allocator_type& __a);
#ifndef _LIBCPP_CXX03_LANG
 __hash_table(__hash_table&& __u)
 _NOEXCEPT_(
 is_nothrow_move_constructible<__bucket_list>::value &&
 is_nothrow_move_constructible<__first_node>::value &&
 is_nothrow_move_constructible<__node_allocator>::value &&
 is_nothrow_move_constructible<hasher>::value &&
 is_nothrow_move_constructible<key_equal>::value);
 __hash_table(__hash_table&& __u, const allocator_type& __a);
#endif // _LIBCPP_CXX03_LANG
 ~__hash_table();

 __hash_table& operator=(const __hash_table& __u);
#ifndef _LIBCPP_CXX03_LANG
 _LIBCPP_INLINE_VISIBILITY
 __hash_table& operator=(__hash_table&& __u)
 _NOEXCEPT_(
 __node_traits::propagate_on_container_move_assignment::value &&
 is_nothrow_move_assignable<__node_allocator>::value &&
 is_nothrow_move_assignable<hasher>::value &&
 is_nothrow_move_assignable<key_equal>::value);
#endif
 template <class _InputIterator>
 void __assign_unique(_InputIterator __first, _InputIterator __last);
 template <class _InputIterator>
 void __assign_multi(_InputIterator __first, _InputIterator __last);

 _LIBCPP_INLINE_VISIBILITY
 size_type max_size() const _NOEXCEPT
 {
 return allocator_traits<__pointer_allocator>::max_size(
 __bucket_list_.get_deleter().__alloc());
 }

 pair<iterator, bool> __node_insert_unique(__node_pointer __nd);
 iterator __node_insert_multi(__node_pointer __nd);
 iterator __node_insert_multi(const_iterator __p,
 __node_pointer __nd);

#ifndef _LIBCPP_CXX03_LANG
 template <class _Key, class ..._Args>
 _LIBCPP_INLINE_VISIBILITY
 pair<iterator, bool> __emplace_unique_key_args(_Key const& __k, _Args&&... __args);

 template <class... _Args>
 _LIBCPP_INLINE_VISIBILITY
 pair<iterator, bool> __emplace_unique_impl(_Args&&... __args);

 template <class _Pp>
 _LIBCPP_INLINE_VISIBILITY
 pair<iterator, bool> __emplace_unique(_Pp&& __x) {
 return __emplace_unique_extract_key(_VSTD::forward<_Pp>(__x),
 __can_extract_key<_Pp, key_type>());
 }

 template <class _First, class _Second>
 _LIBCPP_INLINE_VISIBILITY
 typename enable_if<
 __can_extract_map_key<_First, key_type, __container_value_type>::value,
 pair<iterator, bool>
 >::type __emplace_unique(_First&& __f, _Second&& __s) {
 return __emplace_unique_key_args(__f, _VSTD::forward<_First>(__f),
 _VSTD::forward<_Second>(__s));
 }

 template <class... _Args>
 _LIBCPP_INLINE_VISIBILITY
 pair<iterator, bool> __emplace_unique(_Args&&... __args) {
 return __emplace_unique_impl(_VSTD::forward<_Args>(__args)...);
 }

 template <class _Pp>
 _LIBCPP_INLINE_VISIBILITY
 pair<iterator, bool>
 __emplace_unique_extract_key(_Pp&& __x, __extract_key_fail_tag) {
 return __emplace_unique_impl(_VSTD::forward<_Pp>(__x));
 }
 template <class _Pp>
 _LIBCPP_INLINE_VISIBILITY
 pair<iterator, bool>
 __emplace_unique_extract_key(_Pp&& __x, __extract_key_self_tag) {
 return __emplace_unique_key_args(__x, _VSTD::forward<_Pp>(__x));
 }
 template <class _Pp>
 _LIBCPP_INLINE_VISIBILITY
 pair<iterator, bool>
 __emplace_unique_extract_key(_Pp&& __x, __extract_key_first_tag) {
 return __emplace_unique_key_args(__x.first, _VSTD::forward<_Pp>(__x));
 }

 template <class... _Args>
 _LIBCPP_INLINE_VISIBILITY
 iterator __emplace_multi(_Args&&... __args);
 template <class... _Args>
 _LIBCPP_INLINE_VISIBILITY
 iterator __emplace_hint_multi(const_iterator __p, _Args&&... __args);


 _LIBCPP_INLINE_VISIBILITY
 pair<iterator, bool>
 __insert_unique(__container_value_type&& __x) {
 return __emplace_unique_key_args(_NodeTypes::__get_key(__x), _VSTD::move(__x));
 }

 template <class _Pp, class = typename enable_if<
 !__is_same_uncvref<_Pp, __container_value_type>::value
 >::type>
 _LIBCPP_INLINE_VISIBILITY
 pair<iterator, bool> __insert_unique(_Pp&& __x) {
 return __emplace_unique(_VSTD::forward<_Pp>(__x));
 }

 template <class _Pp>
 _LIBCPP_INLINE_VISIBILITY
 iterator __insert_multi(_Pp&& __x) {
 return __emplace_multi(_VSTD::forward<_Pp>(__x));
 }

 template <class _Pp>
 _LIBCPP_INLINE_VISIBILITY
 iterator __insert_multi(const_iterator __p, _Pp&& __x) {
 return __emplace_hint_multi(__p, _VSTD::forward<_Pp>(__x));
 }

#else // !defined(_LIBCPP_CXX03_LANG)
 template <class _Key, class _Args>
 pair<iterator, bool> __emplace_unique_key_args(_Key const&, _Args& __args);

 iterator __insert_multi(const __container_value_type& __x);
 iterator __insert_multi(const_iterator __p, const __container_value_type& __x);
#endif

 _LIBCPP_INLINE_VISIBILITY
 pair<iterator, bool> __insert_unique(const __container_value_type& __x) {
 return __emplace_unique_key_args(_NodeTypes::__get_key(__x), __x);
 }

 void clear() _NOEXCEPT;
 void rehash(size_type __n);
 _LIBCPP_INLINE_VISIBILITY void reserve(size_type __n)
 {rehash(static_cast<size_type>(ceil(__n / max_load_factor())));}

 _LIBCPP_INLINE_VISIBILITY
 size_type bucket_count() const _NOEXCEPT
 {
 return __bucket_list_.get_deleter().size();
 }

 _LIBCPP_INLINE_VISIBILITY
 iterator begin() _NOEXCEPT;
 _LIBCPP_INLINE_VISIBILITY
 iterator end() _NOEXCEPT;
 _LIBCPP_INLINE_VISIBILITY
 const_iterator begin() const _NOEXCEPT;
 _LIBCPP_INLINE_VISIBILITY
 const_iterator end() const _NOEXCEPT;

 template <class _Key>
 _LIBCPP_INLINE_VISIBILITY
 size_type bucket(const _Key& __k) const
 {
 _LIBCPP_ASSERT(bucket_count() > 0,
 "unordered container::bucket(key) called when bucket_count() == 0");
 return __constrain_hash(hash_function()(__k), bucket_count());
 }

 template <class _Key>
 iterator find(const _Key& __x);
 template <class _Key>
 const_iterator find(const _Key& __x) const;

 typedef __hash_node_destructor<__node_allocator> _Dp;
 typedef unique_ptr<__node, _Dp> __node_holder;

 iterator erase(const_iterator __p);
 iterator erase(const_iterator __first, const_iterator __last);
 template <class _Key>
 size_type __erase_unique(const _Key& __k);
 template <class _Key>
 size_type __erase_multi(const _Key& __k);
 __node_holder remove(const_iterator __p) _NOEXCEPT;

 template <class _Key>
 _LIBCPP_INLINE_VISIBILITY
 size_type __count_unique(const _Key& __k) const;
 template <class _Key>
 size_type __count_multi(const _Key& __k) const;

 template <class _Key>
 pair<iterator, iterator>
 __equal_range_unique(const _Key& __k);
 template <class _Key>
 pair<const_iterator, const_iterator>
 __equal_range_unique(const _Key& __k) const;

 template <class _Key>
 pair<iterator, iterator>
 __equal_range_multi(const _Key& __k);
 template <class _Key>
 pair<const_iterator, const_iterator>
 __equal_range_multi(const _Key& __k) const;

 void swap(__hash_table& __u)
#if _LIBCPP_STD_VER <= 11
 _NOEXCEPT_(
 __is_nothrow_swappable<hasher>::value && __is_nothrow_swappable<key_equal>::value
 && (!allocator_traits<__pointer_allocator>::propagate_on_container_swap::value
 || __is_nothrow_swappable<__pointer_allocator>::value)
 && (!__node_traits::propagate_on_container_swap::value
 || __is_nothrow_swappable<__node_allocator>::value)
 );
#else
 _NOEXCEPT_(__is_nothrow_swappable<hasher>::value && __is_nothrow_swappable<key_equal>::value);
#endif

 _LIBCPP_INLINE_VISIBILITY
 size_type max_bucket_count() const _NOEXCEPT
 {return __pointer_alloc_traits::max_size(__bucket_list_.get_deleter().__alloc());}
 size_type bucket_size(size_type __n) const;
 _LIBCPP_INLINE_VISIBILITY float load_factor() const _NOEXCEPT
 {
 size_type __bc = bucket_count();
 return __bc != 0 ? (float)size() / __bc : 0.f;
 }
 _LIBCPP_INLINE_VISIBILITY void max_load_factor(float __mlf) _NOEXCEPT
 {
 _LIBCPP_ASSERT(__mlf > 0,
 "unordered container::max_load_factor(lf) called with lf <= 0");
 max_load_factor() = _VSTD::max(__mlf, load_factor());
 }

 _LIBCPP_INLINE_VISIBILITY
 local_iterator
 begin(size_type __n)
 {
 _LIBCPP_ASSERT(__n < bucket_count(),
 "unordered container::begin(n) called with n >= bucket_count()");
#if _LIBCPP_DEBUG_LEVEL >= 2
 return local_iterator(__bucket_list_[__n], __n, bucket_count(), this);
#else
 return local_iterator(__bucket_list_[__n], __n, bucket_count());
#endif
 }

 _LIBCPP_INLINE_VISIBILITY
 local_iterator
 end(size_type __n)
 {
 _LIBCPP_ASSERT(__n < bucket_count(),
 "unordered container::end(n) called with n >= bucket_count()");
#if _LIBCPP_DEBUG_LEVEL >= 2
 return local_iterator(nullptr, __n, bucket_count(), this);
#else
 return local_iterator(nullptr, __n, bucket_count());
#endif
 }

 _LIBCPP_INLINE_VISIBILITY
 const_local_iterator
 cbegin(size_type __n) const
 {
 _LIBCPP_ASSERT(__n < bucket_count(),
 "unordered container::cbegin(n) called with n >= bucket_count()");
#if _LIBCPP_DEBUG_LEVEL >= 2
 return const_local_iterator(__bucket_list_[__n], __n, bucket_count(), this);
#else
 return const_local_iterator(__bucket_list_[__n], __n, bucket_count());
#endif
 }

 _LIBCPP_INLINE_VISIBILITY
 const_local_iterator
 cend(size_type __n) const
 {
 _LIBCPP_ASSERT(__n < bucket_count(),
 "unordered container::cend(n) called with n >= bucket_count()");
#if _LIBCPP_DEBUG_LEVEL >= 2
 return const_local_iterator(nullptr, __n, bucket_count(), this);
#else
 return const_local_iterator(nullptr, __n, bucket_count());
#endif
 }

#if _LIBCPP_DEBUG_LEVEL >= 2

 bool __dereferenceable(const const_iterator* __i) const;
 bool __decrementable(const const_iterator* __i) const;
 bool __addable(const const_iterator* __i, ptrdiff_t __n) const;
 bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const;

#endif // _LIBCPP_DEBUG_LEVEL >= 2

private:
 void __rehash(size_type __n);

#ifndef _LIBCPP_CXX03_LANG
 template <class ..._Args>
 __node_holder __construct_node(_Args&& ...__args);

 template <class _First, class ..._Rest>
 __node_holder __construct_node_hash(size_t __hash, _First&& __f, _Rest&&... __rest);
#else // _LIBCPP_CXX03_LANG
 __node_holder __construct_node(const __container_value_type& __v);
 __node_holder __construct_node_hash(size_t __hash, const __container_value_type& __v);
#endif


 _LIBCPP_INLINE_VISIBILITY
 void __copy_assign_alloc(const __hash_table& __u)
 {__copy_assign_alloc(__u, integral_constant<bool,
 __node_traits::propagate_on_container_copy_assignment::value>());}
 void __copy_assign_alloc(const __hash_table& __u, true_type);
 _LIBCPP_INLINE_VISIBILITY
 void __copy_assign_alloc(const __hash_table&, false_type) {}

#ifndef _LIBCPP_CXX03_LANG
 void __move_assign(__hash_table& __u, false_type);
 void __move_assign(__hash_table& __u, true_type)
 _NOEXCEPT_(
 is_nothrow_move_assignable<__node_allocator>::value &&
 is_nothrow_move_assignable<hasher>::value &&
 is_nothrow_move_assignable<key_equal>::value);
 _LIBCPP_INLINE_VISIBILITY
 void __move_assign_alloc(__hash_table& __u)
 _NOEXCEPT_(
 !__node_traits::propagate_on_container_move_assignment::value ||
 (is_nothrow_move_assignable<__pointer_allocator>::value &&
 is_nothrow_move_assignable<__node_allocator>::value))
 {__move_assign_alloc(__u, integral_constant<bool,
 __node_traits::propagate_on_container_move_assignment::value>());}
 _LIBCPP_INLINE_VISIBILITY
 void __move_assign_alloc(__hash_table& __u, true_type)
 _NOEXCEPT_(
 is_nothrow_move_assignable<__pointer_allocator>::value &&
 is_nothrow_move_assignable<__node_allocator>::value)
 {
 __bucket_list_.get_deleter().__alloc() =
 _VSTD::move(__u.__bucket_list_.get_deleter().__alloc());
 __node_alloc() = _VSTD::move(__u.__node_alloc());
 }
 _LIBCPP_INLINE_VISIBILITY
 void __move_assign_alloc(__hash_table&, false_type) _NOEXCEPT {}
#endif // _LIBCPP_CXX03_LANG

 void __deallocate(__node_pointer __np) _NOEXCEPT;
 __node_pointer __detach() _NOEXCEPT;

 template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_map;
 template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_multimap;
};

template <class _Tp, class _Hash, class _Equal, class _Alloc>
inline
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table()
 _NOEXCEPT_(
 is_nothrow_default_constructible<__bucket_list>::value &&
 is_nothrow_default_constructible<__first_node>::value &&
 is_nothrow_default_constructible<__node_allocator>::value &&
 is_nothrow_default_constructible<hasher>::value &&
 is_nothrow_default_constructible<key_equal>::value)
 : __p2_(0),
 __p3_(1.0f)
{
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
inline
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const hasher& __hf,
 const key_equal& __eql)
 : __bucket_list_(nullptr, __bucket_list_deleter()),
 __p1_(),
 __p2_(0, __hf),
 __p3_(1.0f, __eql)
{
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const hasher& __hf,
 const key_equal& __eql,
 const allocator_type& __a)
 : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
 __p1_(__node_allocator(__a)),
 __p2_(0, __hf),
 __p3_(1.0f, __eql)
{
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const allocator_type& __a)
 : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
 __p1_(__node_allocator(__a)),
 __p2_(0),
 __p3_(1.0f)
{
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const __hash_table& __u)
 : __bucket_list_(nullptr,
 __bucket_list_deleter(allocator_traits<__pointer_allocator>::
 select_on_container_copy_construction(
 __u.__bucket_list_.get_deleter().__alloc()), 0)),
 __p1_(allocator_traits<__node_allocator>::
 select_on_container_copy_construction(__u.__node_alloc())),
 __p2_(0, __u.hash_function()),
 __p3_(__u.__p3_)
{
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const __hash_table& __u,
 const allocator_type& __a)
 : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
 __p1_(__node_allocator(__a)),
 __p2_(0, __u.hash_function()),
 __p3_(__u.__p3_)
{
}

#ifndef _LIBCPP_CXX03_LANG

template <class _Tp, class _Hash, class _Equal, class _Alloc>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(__hash_table&& __u)
 _NOEXCEPT_(
 is_nothrow_move_constructible<__bucket_list>::value &&
 is_nothrow_move_constructible<__first_node>::value &&
 is_nothrow_move_constructible<__node_allocator>::value &&
 is_nothrow_move_constructible<hasher>::value &&
 is_nothrow_move_constructible<key_equal>::value)
 : __bucket_list_(_VSTD::move(__u.__bucket_list_)),
 __p1_(_VSTD::move(__u.__p1_)),
 __p2_(_VSTD::move(__u.__p2_)),
 __p3_(_VSTD::move(__u.__p3_))
{
 if (size() > 0)
 {
 __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
 static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
 __u.__p1_.first().__next_ = nullptr;
 __u.size() = 0;
 }
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(__hash_table&& __u,
 const allocator_type& __a)
 : __bucket_list_(nullptr, __bucket_list_deleter(__pointer_allocator(__a), 0)),
 __p1_(__node_allocator(__a)),
 __p2_(0, _VSTD::move(__u.hash_function())),
 __p3_(_VSTD::move(__u.__p3_))
{
 if (__a == allocator_type(__u.__node_alloc()))
 {
 __bucket_list_.reset(__u.__bucket_list_.release());
 __bucket_list_.get_deleter().size() = __u.__bucket_list_.get_deleter().size();
 __u.__bucket_list_.get_deleter().size() = 0;
 if (__u.size() > 0)
 {
 __p1_.first().__next_ = __u.__p1_.first().__next_;
 __u.__p1_.first().__next_ = nullptr;
 __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
 static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
 size() = __u.size();
 __u.size() = 0;
 }
 }
}

#endif // _LIBCPP_CXX03_LANG

template <class _Tp, class _Hash, class _Equal, class _Alloc>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::~__hash_table()
{
 static_assert((is_copy_constructible<key_equal>::value),
 "Predicate must be copy-constructible.");
 static_assert((is_copy_constructible<hasher>::value),
 "Hasher must be copy-constructible.");
 __deallocate(__p1_.first().__next_);
#if _LIBCPP_DEBUG_LEVEL >= 2
 __get_db()->__erase_c(this);
#endif
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
void
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__copy_assign_alloc(
 const __hash_table& __u, true_type)
{
 if (__node_alloc() != __u.__node_alloc())
 {
 clear();
 __bucket_list_.reset();
 __bucket_list_.get_deleter().size() = 0;
 }
 __bucket_list_.get_deleter().__alloc() = __u.__bucket_list_.get_deleter().__alloc();
 __node_alloc() = __u.__node_alloc();
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
__hash_table<_Tp, _Hash, _Equal, _Alloc>&
__hash_table<_Tp, _Hash, _Equal, _Alloc>::operator=(const __hash_table& __u)
{
 if (this != &__u)
 {
 __copy_assign_alloc(__u);
 hash_function() = __u.hash_function();
 key_eq() = __u.key_eq();
 max_load_factor() = __u.max_load_factor();
 __assign_multi(__u.begin(), __u.end());
 }
 return *this;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
void
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__deallocate(__node_pointer __np)
 _NOEXCEPT
{
 __node_allocator& __na = __node_alloc();
 while (__np != nullptr)
 {
 __node_pointer __next = __np->__next_;
#if _LIBCPP_DEBUG_LEVEL >= 2
 __c_node* __c = __get_db()->__find_c_and_lock(this);
 for (__i_node** __p = __c->end_; __p != __c->beg_; )
 {
 --__p;
 iterator* __i = static_cast<iterator*>((*__p)->__i_);
 if (__i->__node_ == __np)
 {
 (*__p)->__c_ = nullptr;
 if (--__c->end_ != __p)
 memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
 }
 }
 __get_db()->unlock();
#endif
 __node_traits::destroy(__na, _NodeTypes::__get_ptr(__np->__value_));
 __node_traits::deallocate(__na, __np, 1);
 __np = __next;
 }
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_pointer
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__detach() _NOEXCEPT
{
 size_type __bc = bucket_count();
 for (size_type __i = 0; __i < __bc; ++__i)
 __bucket_list_[__i] = nullptr;
 size() = 0;
 __node_pointer __cache = __p1_.first().__next_;
 __p1_.first().__next_ = nullptr;
 return __cache;
}

#ifndef _LIBCPP_CXX03_LANG

template <class _Tp, class _Hash, class _Equal, class _Alloc>
void
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(
 __hash_table& __u, true_type)
 _NOEXCEPT_(
 is_nothrow_move_assignable<__node_allocator>::value &&
 is_nothrow_move_assignable<hasher>::value &&
 is_nothrow_move_assignable<key_equal>::value)
{
 clear();
 __bucket_list_.reset(__u.__bucket_list_.release());
 __bucket_list_.get_deleter().size() = __u.__bucket_list_.get_deleter().size();
 __u.__bucket_list_.get_deleter().size() = 0;
 __move_assign_alloc(__u);
 size() = __u.size();
 hash_function() = _VSTD::move(__u.hash_function());
 max_load_factor() = __u.max_load_factor();
 key_eq() = _VSTD::move(__u.key_eq());
 __p1_.first().__next_ = __u.__p1_.first().__next_;
 if (size() > 0)
 {
 __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
 static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
 __u.__p1_.first().__next_ = nullptr;
 __u.size() = 0;
 }
#if _LIBCPP_DEBUG_LEVEL >= 2
 __get_db()->swap(this, &__u);
#endif
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
void
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(
 __hash_table& __u, false_type)
{
 if (__node_alloc() == __u.__node_alloc())
 __move_assign(__u, true_type());
 else
 {
 hash_function() = _VSTD::move(__u.hash_function());
 key_eq() = _VSTD::move(__u.key_eq());
 max_load_factor() = __u.max_load_factor();
 if (bucket_count() != 0)
 {
 __node_pointer __cache = __detach();
#ifndef _LIBCPP_NO_EXCEPTIONS
 try
 {
#endif // _LIBCPP_NO_EXCEPTIONS
 const_iterator __i = __u.begin();
 while (__cache != nullptr && __u.size() != 0)
 {
 __cache->__value_ = _VSTD::move(__u.remove(__i++)->__value_);
 __node_pointer __next = __cache->__next_;
 __node_insert_multi(__cache);
 __cache = __next;
 }
#ifndef _LIBCPP_NO_EXCEPTIONS
 }
 catch (...)
 {
 __deallocate(__cache);
 throw;
 }
#endif // _LIBCPP_NO_EXCEPTIONS
 __deallocate(__cache);
 }
 const_iterator __i = __u.begin();
 while (__u.size() != 0)
 {
 __node_holder __h = __construct_node(_NodeTypes::__move(__u.remove(__i++)->__value_));
 __node_insert_multi(__h.get());
 __h.release();
 }
 }
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
inline
__hash_table<_Tp, _Hash, _Equal, _Alloc>&
__hash_table<_Tp, _Hash, _Equal, _Alloc>::operator=(__hash_table&& __u)
 _NOEXCEPT_(
 __node_traits::propagate_on_container_move_assignment::value &&
 is_nothrow_move_assignable<__node_allocator>::value &&
 is_nothrow_move_assignable<hasher>::value &&
 is_nothrow_move_assignable<key_equal>::value)
{
 __move_assign(__u, integral_constant<bool,
 __node_traits::propagate_on_container_move_assignment::value>());
 return *this;
}

#endif // _LIBCPP_CXX03_LANG

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _InputIterator>
void
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__assign_unique(_InputIterator __first,
 _InputIterator __last)
{
 typedef iterator_traits<_InputIterator> _ITraits;
 typedef typename _ITraits::value_type _ItValueType;
 static_assert((is_same<_ItValueType, __container_value_type>::value),
 "__assign_unique may only be called with the containers value type");

 if (bucket_count() != 0)
 {
 __node_pointer __cache = __detach();
#ifndef _LIBCPP_NO_EXCEPTIONS
 try
 {
#endif // _LIBCPP_NO_EXCEPTIONS
 for (; __cache != nullptr && __first != __last; ++__first)
 {
 __cache->__value_ = *__first;
 __node_pointer __next = __cache->__next_;
 __node_insert_unique(__cache);
 __cache = __next;
 }
#ifndef _LIBCPP_NO_EXCEPTIONS
 }
 catch (...)
 {
 __deallocate(__cache);
 throw;
 }
#endif // _LIBCPP_NO_EXCEPTIONS
 __deallocate(__cache);
 }
 for (; __first != __last; ++__first)
 __insert_unique(*__first);
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _InputIterator>
void
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__assign_multi(_InputIterator __first,
 _InputIterator __last)
{
 typedef iterator_traits<_InputIterator> _ITraits;
 typedef typename _ITraits::value_type _ItValueType;
 static_assert((is_same<_ItValueType, __container_value_type>::value ||
 is_same<_ItValueType, __node_value_type>::value),
 "__assign_multi may only be called with the containers value type"
 " or the nodes value type");
 if (bucket_count() != 0)
 {
 __node_pointer __cache = __detach();
#ifndef _LIBCPP_NO_EXCEPTIONS
 try
 {
#endif // _LIBCPP_NO_EXCEPTIONS
 for (; __cache != nullptr && __first != __last; ++__first)
 {
 __cache->__value_ = *__first;
 __node_pointer __next = __cache->__next_;
 __node_insert_multi(__cache);
 __cache = __next;
 }
#ifndef _LIBCPP_NO_EXCEPTIONS
 }
 catch (...)
 {
 __deallocate(__cache);
 throw;
 }
#endif // _LIBCPP_NO_EXCEPTIONS
 __deallocate(__cache);
 }
 for (; __first != __last; ++__first)
 __insert_multi(_NodeTypes::__get_value(*__first));
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
inline
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::begin() _NOEXCEPT
{
#if _LIBCPP_DEBUG_LEVEL >= 2
 return iterator(__p1_.first().__next_, this);
#else
 return iterator(__p1_.first().__next_);
#endif
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
inline
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::end() _NOEXCEPT
{
#if _LIBCPP_DEBUG_LEVEL >= 2
 return iterator(nullptr, this);
#else
 return iterator(nullptr);
#endif
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
inline
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::begin() const _NOEXCEPT
{
#if _LIBCPP_DEBUG_LEVEL >= 2
 return const_iterator(__p1_.first().__next_, this);
#else
 return const_iterator(__p1_.first().__next_);
#endif
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
inline
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::end() const _NOEXCEPT
{
#if _LIBCPP_DEBUG_LEVEL >= 2
 return const_iterator(nullptr, this);
#else
 return const_iterator(nullptr);
#endif
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
void
__hash_table<_Tp, _Hash, _Equal, _Alloc>::clear() _NOEXCEPT
{
 if (size() > 0)
 {
 __deallocate(__p1_.first().__next_);
 __p1_.first().__next_ = nullptr;
 size_type __bc = bucket_count();
 for (size_type __i = 0; __i < __bc; ++__i)
 __bucket_list_[__i] = nullptr;
 size() = 0;
 }
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_unique(__node_pointer __nd)
{
 __nd->__hash_ = hash_function()(__nd->__value_);
 size_type __bc = bucket_count();
 bool __inserted = false;
 __node_pointer __ndptr;
 size_t __chash;
 if (__bc != 0)
 {
 __chash = __constrain_hash(__nd->__hash_, __bc);
 __ndptr = __bucket_list_[__chash];
 if (__ndptr != nullptr)
 {
 for (__ndptr = __ndptr->__next_; __ndptr != nullptr &&
 __constrain_hash(__ndptr->__hash_, __bc) == __chash;
 __ndptr = __ndptr->__next_)
 {
 if (key_eq()(__ndptr->__value_, __nd->__value_))
 goto __done;
 }
 }
 }
 {
 if (size()+1 > __bc * max_load_factor() || __bc == 0)
 {
 rehash(_VSTD::max<size_type>(2 * __bc + !__is_hash_power2(__bc),
 size_type(ceil(float(size() + 1) / max_load_factor()))));
 __bc = bucket_count();
 __chash = __constrain_hash(__nd->__hash_, __bc);
 }
 // insert_after __bucket_list_[__chash], or __first_node if bucket is null
 __node_pointer __pn = __bucket_list_[__chash];
 if (__pn == nullptr)
 {
 __pn = static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
 __nd->__next_ = __pn->__next_;
 __pn->__next_ = __nd;
 // fix up __bucket_list_
 __bucket_list_[__chash] = __pn;
 if (__nd->__next_ != nullptr)
 __bucket_list_[__constrain_hash(__nd->__next_->__hash_, __bc)] = __nd;
 }
 else
 {
 __nd->__next_ = __pn->__next_;
 __pn->__next_ = __nd;
 }
 __ndptr = __nd;
 // increment size
 ++size();
 __inserted = true;
 }
__done:
#if _LIBCPP_DEBUG_LEVEL >= 2
 return pair<iterator, bool>(iterator(__ndptr, this), __inserted);
#else
 return pair<iterator, bool>(iterator(__ndptr), __inserted);
#endif
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(__node_pointer __cp)
{
 __cp->__hash_ = hash_function()(__cp->__value_);
 size_type __bc = bucket_count();
 if (size()+1 > __bc * max_load_factor() || __bc == 0)
 {
 rehash(_VSTD::max<size_type>(2 * __bc + !__is_hash_power2(__bc),
 size_type(ceil(float(size() + 1) / max_load_factor()))));
 __bc = bucket_count();
 }
 size_t __chash = __constrain_hash(__cp->__hash_, __bc);
 __node_pointer __pn = __bucket_list_[__chash];
 if (__pn == nullptr)
 {
 __pn = static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
 __cp->__next_ = __pn->__next_;
 __pn->__next_ = __cp;
 // fix up __bucket_list_
 __bucket_list_[__chash] = __pn;
 if (__cp->__next_ != nullptr)
 __bucket_list_[__constrain_hash(__cp->__next_->__hash_, __bc)] = __cp;
 }
 else
 {
 for (bool __found = false; __pn->__next_ != nullptr &&
 __constrain_hash(__pn->__next_->__hash_, __bc) == __chash;
 __pn = __pn->__next_)
 {
 // __found key_eq() action
 // false false loop
 // true true loop
 // false true set __found to true
 // true false break
 if (__found != (__pn->__next_->__hash_ == __cp->__hash_ &&
 key_eq()(__pn->__next_->__value_, __cp->__value_)))
 {
 if (!__found)
 __found = true;
 else
 break;
 }
 }
 __cp->__next_ = __pn->__next_;
 __pn->__next_ = __cp;
 if (__cp->__next_ != nullptr)
 {
 size_t __nhash = __constrain_hash(__cp->__next_->__hash_, __bc);
 if (__nhash != __chash)
 __bucket_list_[__nhash] = __cp;
 }
 }
 ++size();
#if _LIBCPP_DEBUG_LEVEL >= 2
 return iterator(__cp, this);
#else
 return iterator(__cp);
#endif
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(
 const_iterator __p, __node_pointer __cp)
{
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
 "unordered container::emplace_hint(const_iterator, args...) called with an iterator not"
 " referring to this unordered container");
#endif
 if (__p != end() && key_eq()(*__p, __cp->__value_))
 {
 __node_pointer __np = __p.__node_;
 __cp->__hash_ = __np->__hash_;
 size_type __bc = bucket_count();
 if (size()+1 > __bc * max_load_factor() || __bc == 0)
 {
 rehash(_VSTD::max<size_type>(2 * __bc + !__is_hash_power2(__bc),
 size_type(ceil(float(size() + 1) / max_load_factor()))));
 __bc = bucket_count();
 }
 size_t __chash = __constrain_hash(__cp->__hash_, __bc);
 __node_pointer __pp = __bucket_list_[__chash];
 while (__pp->__next_ != __np)
 __pp = __pp->__next_;
 __cp->__next_ = __np;
 __pp->__next_ = __cp;
 ++size();
#if _LIBCPP_DEBUG_LEVEL >= 2
 return iterator(__cp, this);
#else
 return iterator(__cp);
#endif
 }
 return __node_insert_multi(__cp);
}



#ifndef _LIBCPP_CXX03_LANG
template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key, class ..._Args>
_LIBCPP_INLINE_VISIBILITY
pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique_key_args(_Key const& __k, _Args&&... __args)
#else
template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key, class _Args>
_LIBCPP_INLINE_VISIBILITY
pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique_key_args(_Key const& __k, _Args& __args)
#endif
{

 size_t __hash = hash_function()(__k);
 size_type __bc = bucket_count();
 bool __inserted = false;
 __node_pointer __nd;
 size_t __chash;
 if (__bc != 0)
 {
 __chash = __constrain_hash(__hash, __bc);
 __nd = __bucket_list_[__chash];
 if (__nd != nullptr)
 {
 for (__nd = __nd->__next_; __nd != nullptr &&
 __constrain_hash(__nd->__hash_, __bc) == __chash;
 __nd = __nd->__next_)
 {
 if (key_eq()(__nd->__value_, __k))
 goto __done;
 }
 }
 }
 {
#ifndef _LIBCPP_CXX03_LANG
 __node_holder __h = __construct_node_hash(__hash, _VSTD::forward<_Args>(__args)...);
#else
 __node_holder __h = __construct_node_hash(__hash, __args);
#endif
 if (size()+1 > __bc * max_load_factor() || __bc == 0)
 {
 rehash(_VSTD::max<size_type>(2 * __bc + !__is_hash_power2(__bc),
 size_type(ceil(float(size() + 1) / max_load_factor()))));
 __bc = bucket_count();
 __chash = __constrain_hash(__hash, __bc);
 }
 // insert_after __bucket_list_[__chash], or __first_node if bucket is null
 __node_pointer __pn = __bucket_list_[__chash];
 if (__pn == nullptr)
 {
 __pn = static_cast<__node_pointer>(static_cast<__void_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first())));
 __h->__next_ = __pn->__next_;
 __pn->__next_ = __h.get();
 // fix up __bucket_list_
 __bucket_list_[__chash] = __pn;
 if (__h->__next_ != nullptr)
 __bucket_list_[__constrain_hash(__h->__next_->__hash_, __bc)] = __h.get();
 }
 else
 {
 __h->__next_ = __pn->__next_;
 __pn->__next_ = __h.get();
 }
 __nd = __h.release();
 // increment size
 ++size();
 __inserted = true;
 }
__done:
#if _LIBCPP_DEBUG_LEVEL >= 2
 return pair<iterator, bool>(iterator(__nd, this), __inserted);
#else
 return pair<iterator, bool>(iterator(__nd), __inserted);
#endif
}

#ifndef _LIBCPP_CXX03_LANG

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class... _Args>
pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique_impl(_Args&&... __args)
{
 __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
 pair<iterator, bool> __r = __node_insert_unique(__h.get());
 if (__r.second)
 __h.release();
 return __r;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class... _Args>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_multi(_Args&&... __args)
{
 __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
 iterator __r = __node_insert_multi(__h.get());
 __h.release();
 return __r;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class... _Args>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_hint_multi(
 const_iterator __p, _Args&&... __args)
{
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
 "unordered container::emplace_hint(const_iterator, args...) called with an iterator not"
 " referring to this unordered container");
#endif
 __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
 iterator __r = __node_insert_multi(__p, __h.get());
 __h.release();
 return __r;
}

#else // _LIBCPP_CXX03_LANG

template <class _Tp, class _Hash, class _Equal, class _Alloc>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__insert_multi(const __container_value_type& __x)
{
 __node_holder __h = __construct_node(__x);
 iterator __r = __node_insert_multi(__h.get());
 __h.release();
 return __r;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__insert_multi(const_iterator __p,
 const __container_value_type& __x)
{
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
 "unordered container::insert(const_iterator, lvalue) called with an iterator not"
 " referring to this unordered container");
#endif
 __node_holder __h = __construct_node(__x);
 iterator __r = __node_insert_multi(__p, __h.get());
 __h.release();
 return __r;
}

#endif // _LIBCPP_CXX03_LANG

template <class _Tp, class _Hash, class _Equal, class _Alloc>
void
__hash_table<_Tp, _Hash, _Equal, _Alloc>::rehash(size_type __n)
{
 if (__n == 1)
 __n = 2;
 else if (__n & (__n - 1))
 __n = __next_prime(__n);
 size_type __bc = bucket_count();
 if (__n > __bc)
 __rehash(__n);
 else if (__n < __bc)
 {
 __n = _VSTD::max<size_type>
 (
 __n,
 __is_hash_power2(__bc) ? __next_hash_pow2(size_t(ceil(float(size()) / max_load_factor()))) :
 __next_prime(size_t(ceil(float(size()) / max_load_factor())))
 );
 if (__n < __bc)
 __rehash(__n);
 }
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
void
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__rehash(size_type __nbc)
{
#if _LIBCPP_DEBUG_LEVEL >= 2
 __get_db()->__invalidate_all(this);
#endif // _LIBCPP_DEBUG_LEVEL >= 2
 __pointer_allocator& __npa = __bucket_list_.get_deleter().__alloc();
 __bucket_list_.reset(__nbc > 0 ?
 __pointer_alloc_traits::allocate(__npa, __nbc) : nullptr);
 __bucket_list_.get_deleter().size() = __nbc;
 if (__nbc > 0)
 {
 for (size_type __i = 0; __i < __nbc; ++__i)
 __bucket_list_[__i] = nullptr;
 __node_pointer __pp(static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first())));
 __node_pointer __cp = __pp->__next_;
 if (__cp != nullptr)
 {
 size_type __chash = __constrain_hash(__cp->__hash_, __nbc);
 __bucket_list_[__chash] = __pp;
 size_type __phash = __chash;
 for (__pp = __cp, __cp = __cp->__next_; __cp != nullptr;
 __cp = __pp->__next_)
 {
 __chash = __constrain_hash(__cp->__hash_, __nbc);
 if (__chash == __phash)
 __pp = __cp;
 else
 {
 if (__bucket_list_[__chash] == nullptr)
 {
 __bucket_list_[__chash] = __pp;
 __pp = __cp;
 __phash = __chash;
 }
 else
 {
 __node_pointer __np = __cp;
 for (; __np->__next_ != nullptr &&
 key_eq()(__cp->__value_, __np->__next_->__value_);
 __np = __np->__next_)
 ;
 __pp->__next_ = __np->__next_;
 __np->__next_ = __bucket_list_[__chash]->__next_;
 __bucket_list_[__chash]->__next_ = __cp;

 }
 }
 }
 }
 }
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::find(const _Key& __k)
{
 size_t __hash = hash_function()(__k);
 size_type __bc = bucket_count();
 if (__bc != 0)
 {
 size_t __chash = __constrain_hash(__hash, __bc);
 __node_pointer __nd = __bucket_list_[__chash];
 if (__nd != nullptr)
 {
 for (__nd = __nd->__next_; __nd != nullptr &&
 (__nd->__hash_ == __hash
 || __constrain_hash(__nd->__hash_, __bc) == __chash);
 __nd = __nd->__next_)
 {
 if ((__nd->__hash_ == __hash) && key_eq()(__nd->__value_, __k))
#if _LIBCPP_DEBUG_LEVEL >= 2
 return iterator(__nd, this);
#else
 return iterator(__nd);
#endif
 }
 }
 }
 return end();
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::find(const _Key& __k) const
{
 size_t __hash = hash_function()(__k);
 size_type __bc = bucket_count();
 if (__bc != 0)
 {
 size_t __chash = __constrain_hash(__hash, __bc);
 __node_const_pointer __nd = __bucket_list_[__chash];
 if (__nd != nullptr)
 {
 for (__nd = __nd->__next_; __nd != nullptr &&
 (__hash == __nd->__hash_ || __constrain_hash(__nd->__hash_, __bc) == __chash);
 __nd = __nd->__next_)
 {
 if ((__nd->__hash_ == __hash) && key_eq()(__nd->__value_, __k))
#if _LIBCPP_DEBUG_LEVEL >= 2
 return const_iterator(__nd, this);
#else
 return const_iterator(__nd);
#endif
 }
 }

 }
 return end();
}

#ifndef _LIBCPP_CXX03_LANG

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class ..._Args>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__construct_node(_Args&& ...__args)
{
 static_assert(!__is_hash_value_type<_Args...>::value,
 "Construct cannot be called with a hash value type");
 __node_allocator& __na = __node_alloc();
 __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
 __node_traits::construct(__na, _NodeTypes::__get_ptr(__h->__value_), _VSTD::forward<_Args>(__args)...);
 __h.get_deleter().__value_constructed = true;
 __h->__hash_ = hash_function()(__h->__value_);
 __h->__next_ = nullptr;
 return __h;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _First, class ..._Rest>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__construct_node_hash(
 size_t __hash, _First&& __f, _Rest&& ...__rest)
{
 static_assert(!__is_hash_value_type<_First, _Rest...>::value,
 "Construct cannot be called with a hash value type");
 __node_allocator& __na = __node_alloc();
 __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
 __node_traits::construct(__na, _NodeTypes::__get_ptr(__h->__value_),
 _VSTD::forward<_First>(__f),
 _VSTD::forward<_Rest>(__rest)...);
 __h.get_deleter().__value_constructed = true;
 __h->__hash_ = __hash;
 __h->__next_ = nullptr;
 return __h;
}

#else // _LIBCPP_CXX03_LANG

template <class _Tp, class _Hash, class _Equal, class _Alloc>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__construct_node(const __container_value_type& __v)
{
 __node_allocator& __na = __node_alloc();
 __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
 __node_traits::construct(__na, _NodeTypes::__get_ptr(__h->__value_), __v);
 __h.get_deleter().__value_constructed = true;
 __h->__hash_ = hash_function()(__h->__value_);
 __h->__next_ = nullptr;
 return _LIBCPP_EXPLICIT_MOVE(__h); // explicitly moved for C++03
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__construct_node_hash(size_t __hash,
 const __container_value_type& __v)
{
 __node_allocator& __na = __node_alloc();
 __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
 __node_traits::construct(__na, _NodeTypes::__get_ptr(__h->__value_), __v);
 __h.get_deleter().__value_constructed = true;
 __h->__hash_ = __hash;
 __h->__next_ = nullptr;
 return _LIBCPP_EXPLICIT_MOVE(__h); // explicitly moved for C++03
}

#endif // _LIBCPP_CXX03_LANG

template <class _Tp, class _Hash, class _Equal, class _Alloc>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __p)
{
 __node_pointer __np = __p.__node_;
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
 "unordered container erase(iterator) called with an iterator not"
 " referring to this container");
 _LIBCPP_ASSERT(__p != end(),
 "unordered container erase(iterator) called with a non-dereferenceable iterator");
 iterator __r(__np, this);
#else
 iterator __r(__np);
#endif
 ++__r;
 remove(__p);
 return __r;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
__hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __first,
 const_iterator __last)
{
#if _LIBCPP_DEBUG_LEVEL >= 2
 _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__first) == this,
 "unodered container::erase(iterator, iterator) called with an iterator not"
 " referring to this unodered container");
 _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__last) == this,
 "unodered container::erase(iterator, iterator) called with an iterator not"
 " referring to this unodered container");
#endif
 for (const_iterator __p = __first; __first != __last; __p = __first)
 {
 ++__first;
 erase(__p);
 }
 __node_pointer __np = __last.__node_;
#if _LIBCPP_DEBUG_LEVEL >= 2
 return iterator (__np, this);
#else
 return iterator (__np);
#endif
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__erase_unique(const _Key& __k)
{
 iterator __i = find(__k);
 if (__i == end())
 return 0;
 erase(__i);
 return 1;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__erase_multi(const _Key& __k)
{
 size_type __r = 0;
 iterator __i = find(__k);
 if (__i != end())
 {
 iterator __e = end();
 do
 {
 erase(__i++);
 ++__r;
 } while (__i != __e && key_eq()(*__i, __k));
 }
 return __r;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
__hash_table<_Tp, _Hash, _Equal, _Alloc>::remove(const_iterator __p) _NOEXCEPT
{
 // current node
 __node_pointer __cn = __p.__node_;
 size_type __bc = bucket_count();
 size_t __chash = __constrain_hash(__cn->__hash_, __bc);
 // find previous node
 __node_pointer __pn = __bucket_list_[__chash];
 for (; __pn->__next_ != __cn; __pn = __pn->__next_)
 ;
 // Fix up __bucket_list_
 // if __pn is not in same bucket (before begin is not in same bucket) &&
 // if __cn->__next_ is not in same bucket (nullptr is not in same bucket)
 if (__pn == static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()))
 || __constrain_hash(__pn->__hash_, __bc) != __chash)
 {
 if (__cn->__next_ == nullptr || __constrain_hash(__cn->__next_->__hash_, __bc) != __chash)
 __bucket_list_[__chash] = nullptr;
 }
 // if __cn->__next_ is not in same bucket (nullptr is in same bucket)
 if (__cn->__next_ != nullptr)
 {
 size_t __nhash = __constrain_hash(__cn->__next_->__hash_, __bc);
 if (__nhash != __chash)
 __bucket_list_[__nhash] = __pn;
 }
 // remove __cn
 __pn->__next_ = __cn->__next_;
 __cn->__next_ = nullptr;
 --size();
#if _LIBCPP_DEBUG_LEVEL >= 2
 __c_node* __c = __get_db()->__find_c_and_lock(this);
 for (__i_node** __p = __c->end_; __p != __c->beg_; )
 {
 --__p;
 iterator* __i = static_cast<iterator*>((*__p)->__i_);
 if (__i->__node_ == __cn)
 {
 (*__p)->__c_ = nullptr;
 if (--__c->end_ != __p)
 memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
 }
 }
 __get_db()->unlock();
#endif
 return __node_holder(__cn, _Dp(__node_alloc(), true));
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key>
inline
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__count_unique(const _Key& __k) const
{
 return static_cast<size_type>(find(__k) != end());
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__count_multi(const _Key& __k) const
{
 size_type __r = 0;
 const_iterator __i = find(__k);
 if (__i != end())
 {
 const_iterator __e = end();
 do
 {
 ++__i;
 ++__r;
 } while (__i != __e && key_eq()(*__i, __k));
 }
 return __r;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key>
pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator,
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_unique(
 const _Key& __k)
{
 iterator __i = find(__k);
 iterator __j = __i;
 if (__i != end())
 ++__j;
 return pair<iterator, iterator>(__i, __j);
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key>
pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator,
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_unique(
 const _Key& __k) const
{
 const_iterator __i = find(__k);
 const_iterator __j = __i;
 if (__i != end())
 ++__j;
 return pair<const_iterator, const_iterator>(__i, __j);
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key>
pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator,
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_multi(
 const _Key& __k)
{
 iterator __i = find(__k);
 iterator __j = __i;
 if (__i != end())
 {
 iterator __e = end();
 do
 {
 ++__j;
 } while (__j != __e && key_eq()(*__j, __k));
 }
 return pair<iterator, iterator>(__i, __j);
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
template <class _Key>
pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator,
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_multi(
 const _Key& __k) const
{
 const_iterator __i = find(__k);
 const_iterator __j = __i;
 if (__i != end())
 {
 const_iterator __e = end();
 do
 {
 ++__j;
 } while (__j != __e && key_eq()(*__j, __k));
 }
 return pair<const_iterator, const_iterator>(__i, __j);
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
void
__hash_table<_Tp, _Hash, _Equal, _Alloc>::swap(__hash_table& __u)
#if _LIBCPP_STD_VER <= 11
 _NOEXCEPT_(
 __is_nothrow_swappable<hasher>::value && __is_nothrow_swappable<key_equal>::value
 && (!allocator_traits<__pointer_allocator>::propagate_on_container_swap::value
 || __is_nothrow_swappable<__pointer_allocator>::value)
 && (!__node_traits::propagate_on_container_swap::value
 || __is_nothrow_swappable<__node_allocator>::value)
 )
#else
 _NOEXCEPT_(__is_nothrow_swappable<hasher>::value && __is_nothrow_swappable<key_equal>::value)
#endif
{
 {
 __node_pointer_pointer __npp = __bucket_list_.release();
 __bucket_list_.reset(__u.__bucket_list_.release());
 __u.__bucket_list_.reset(__npp);
 }
 _VSTD::swap(__bucket_list_.get_deleter().size(), __u.__bucket_list_.get_deleter().size());
 __swap_allocator(__bucket_list_.get_deleter().__alloc(),
 __u.__bucket_list_.get_deleter().__alloc());
 __swap_allocator(__node_alloc(), __u.__node_alloc());
 _VSTD::swap(__p1_.first().__next_, __u.__p1_.first().__next_);
 __p2_.swap(__u.__p2_);
 __p3_.swap(__u.__p3_);
 if (size() > 0)
 __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
 static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
 if (__u.size() > 0)
 __u.__bucket_list_[__constrain_hash(__u.__p1_.first().__next_->__hash_, __u.bucket_count())] =
 static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__u.__p1_.first()));
#if _LIBCPP_DEBUG_LEVEL >= 2
 __get_db()->swap(this, &__u);
#endif
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
__hash_table<_Tp, _Hash, _Equal, _Alloc>::bucket_size(size_type __n) const
{
 _LIBCPP_ASSERT(__n < bucket_count(),
 "unordered container::bucket_size(n) called with n >= bucket_count()");
 __node_const_pointer __np = __bucket_list_[__n];
 size_type __bc = bucket_count();
 size_type __r = 0;
 if (__np != nullptr)
 {
 for (__np = __np->__next_; __np != nullptr &&
 __constrain_hash(__np->__hash_, __bc) == __n;
 __np = __np->__next_, ++__r)
 ;
 }
 return __r;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
inline _LIBCPP_INLINE_VISIBILITY
void
swap(__hash_table<_Tp, _Hash, _Equal, _Alloc>& __x,
 __hash_table<_Tp, _Hash, _Equal, _Alloc>& __y)
 _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
{
 __x.swap(__y);
}

#if _LIBCPP_DEBUG_LEVEL >= 2

template <class _Tp, class _Hash, class _Equal, class _Alloc>
bool
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__dereferenceable(const const_iterator* __i) const
{
 return __i->__node_ != nullptr;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
bool
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__decrementable(const const_iterator*) const
{
 return false;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
bool
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__addable(const const_iterator*, ptrdiff_t) const
{
 return false;
}

template <class _Tp, class _Hash, class _Equal, class _Alloc>
bool
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__subscriptable(const const_iterator*, ptrdiff_t) const
{
 return false;
}

#endif // _LIBCPP_DEBUG_LEVEL >= 2
_LIBCPP_END_NAMESPACE_STD

#endif // _LIBCPP__HASH_TABLE