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 // Copyright (C) 2003-2004 Jeremy B. Maitin-Shepard.
 // Copyright (C) 2005-2011 Daniel James.
 // Copyright (C) 2022-2023 Christian Mazakas
 // Copyright (C) 2024 Joaquin M Lopez Munoz.
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 
 //  See http://www.boost.org/libs/unordered for documentation
 
 #ifndef BOOST_UNORDERED_UNORDERED_MAP_HPP_INCLUDED
 #define BOOST_UNORDERED_UNORDERED_MAP_HPP_INCLUDED
 
 #include <boost/config.hpp>
 #if defined(BOOST_HAS_PRAGMA_ONCE)
 #pragma once
 #endif
 
 #include <boost/unordered/detail/map.hpp>
 #include <boost/unordered/detail/serialize_fca_container.hpp>
 #include <boost/unordered/detail/throw_exception.hpp>
 #include <boost/unordered/detail/type_traits.hpp>
 
 #include <boost/container_hash/hash.hpp>
 
 #include <initializer_list>
 
 #if defined(BOOST_MSVC)
 #pragma warning(push)
 // conditional expression is constant
 #pragma warning(disable : 4127)
 #if BOOST_MSVC >= 1400
 // the inline specifier cannot be used when a friend declaration refers to a
 // specialization of a function template
 #pragma warning(disable : 4396)
 #endif
 #endif
 
 namespace boost {
   namespace unordered {
     template <class K, class T, class H, class P, class A> class unordered_map
     {
       template <typename, typename, typename, typename, typename>
       friend class unordered_multimap;
 
     public:
       typedef K key_type;
       typedef T mapped_type;
       typedef std::pair<const K, T> value_type;
       typedef typename boost::unordered::detail::type_identity<H>::type hasher;
       typedef
         typename boost::unordered::detail::type_identity<P>::type key_equal;
       typedef typename boost::unordered::detail::type_identity<A>::type
         allocator_type;
 
     private:
       typedef boost::unordered::detail::map<A, K, T, H, P> types;
       typedef typename types::value_allocator_traits value_allocator_traits;
       typedef typename types::table table;
 
     public:
       typedef typename value_allocator_traits::pointer pointer;
       typedef typename value_allocator_traits::const_pointer const_pointer;
 
       typedef value_type& reference;
       typedef value_type const& const_reference;
 
       typedef std::size_t size_type;
       typedef std::ptrdiff_t difference_type;
 
       typedef typename table::iterator iterator;
       typedef typename table::c_iterator const_iterator;
       typedef typename table::l_iterator local_iterator;
       typedef typename table::cl_iterator const_local_iterator;
       typedef typename types::node_type node_type;
       typedef typename types::insert_return_type insert_return_type;
 
     private:
       table table_;
 
     public:
       // constructors
 
       unordered_map();
 
       explicit unordered_map(size_type, const hasher& = hasher(),
         const key_equal& = key_equal(),
         const allocator_type& = allocator_type());
 
       template <class InputIt>
       unordered_map(InputIt, InputIt,
         size_type = boost::unordered::detail::default_bucket_count,
         const hasher& = hasher(), const key_equal& = key_equal(),
         const allocator_type& = allocator_type());
 
       unordered_map(unordered_map const&);
 
       unordered_map(unordered_map&& other)
         noexcept(table::nothrow_move_constructible)
           : table_(other.table_, boost::unordered::detail::move_tag())
       {
         // The move is done in table_
       }
 
       explicit unordered_map(allocator_type const&);
 
       unordered_map(unordered_map const&, allocator_type const&);
 
       unordered_map(unordered_map&&, allocator_type const&);
 
       unordered_map(std::initializer_list<value_type>,
         size_type = boost::unordered::detail::default_bucket_count,
         const hasher& = hasher(), const key_equal& l = key_equal(),
         const allocator_type& = allocator_type());
 
       explicit unordered_map(size_type, const allocator_type&);
 
       explicit unordered_map(size_type, const hasher&, const allocator_type&);
 
       template <class InputIterator>
       unordered_map(InputIterator, InputIterator, const allocator_type&);
 
       template <class InputIt>
       unordered_map(InputIt, InputIt, size_type, const allocator_type&);
 
       template <class InputIt>
       unordered_map(
         InputIt, InputIt, size_type, const hasher&, const allocator_type&);
 
       unordered_map(std::initializer_list<value_type>, const allocator_type&);
 
       unordered_map(
         std::initializer_list<value_type>, size_type, const allocator_type&);
 
       unordered_map(std::initializer_list<value_type>, size_type, const hasher&,
         const allocator_type&);
 
       // Destructor
 
       ~unordered_map() noexcept;
 
       // Assign
 
       unordered_map& operator=(unordered_map const& x)
       {
         table_.assign(x.table_, std::true_type());
         return *this;
       }
 
       unordered_map& operator=(unordered_map&& x)
         noexcept(value_allocator_traits::is_always_equal::value&&
             std::is_nothrow_move_assignable<H>::value&&
               std::is_nothrow_move_assignable<P>::value)
       {
         table_.move_assign(x.table_, std::true_type());
         return *this;
       }
 
       unordered_map& operator=(std::initializer_list<value_type>);
 
       allocator_type get_allocator() const noexcept
       {
         return allocator_type(table_.node_alloc());
       }
 
       //       // iterators
 
       iterator begin() noexcept { return table_.begin(); }
 
       const_iterator begin() const noexcept
       {
         return const_iterator(table_.begin());
       }
 
       iterator end() noexcept { return iterator(); }
 
       const_iterator end() const noexcept { return const_iterator(); }
 
       const_iterator cbegin() const noexcept
       {
         return const_iterator(table_.begin());
       }
 
       const_iterator cend() const noexcept { return const_iterator(); }
 
       // size and capacity
 
       BOOST_ATTRIBUTE_NODISCARD bool empty() const noexcept
       {
         return table_.size_ == 0;
       }
 
       size_type size() const noexcept { return table_.size_; }
 
       size_type max_size() const noexcept;
 
       // emplace
 
       template <class... Args> std::pair<iterator, bool> emplace(Args&&... args)
       {
         return table_.emplace_unique(
           table::extractor::extract(std::forward<Args>(args)...),
           std::forward<Args>(args)...);
       }
 
       template <class... Args>
       iterator emplace_hint(const_iterator hint, Args&&... args)
       {
         return table_.emplace_hint_unique(hint,
           table::extractor::extract(std::forward<Args>(args)...),
           std::forward<Args>(args)...);
       }
 
       std::pair<iterator, bool> insert(value_type const& x)
       {
         return this->emplace(x);
       }
 
       std::pair<iterator, bool> insert(value_type&& x)
       {
         return this->emplace(std::move(x));
       }
 
       template <class P2>
       typename boost::enable_if<std::is_constructible<value_type, P2&&>,
         std::pair<iterator, bool> >::type
       insert(P2&& obj)
       {
         return this->emplace(std::forward<P2>(obj));
       }
 
       iterator insert(const_iterator hint, value_type const& x)
       {
         return this->emplace_hint(hint, x);
       }
 
       iterator insert(const_iterator hint, value_type&& x)
       {
         return this->emplace_hint(hint, std::move(x));
       }
 
       template <class P2>
       typename boost::enable_if<std::is_constructible<value_type, P2&&>,
         iterator>::type
       insert(const_iterator hint, P2&& obj)
       {
         return this->emplace_hint(hint, std::forward<P2>(obj));
       }
 
       template <class InputIt> void insert(InputIt, InputIt);
 
       void insert(std::initializer_list<value_type>);
 
       // extract
 
       node_type extract(const_iterator position)
       {
         return node_type(
           table_.extract_by_iterator_unique(position),
           allocator_type(table_.node_alloc()));
       }
 
       node_type extract(const key_type& k)
       {
         return node_type(
           table_.extract_by_key_impl(k),
           allocator_type(table_.node_alloc()));
       }
 
       template <class Key>
       typename boost::enable_if_c<
         detail::transparent_non_iterable<Key, unordered_map>::value,
         node_type>::type
       extract(Key&& k)
       {
         return node_type(
           table_.extract_by_key_impl(std::forward<Key>(k)),
           allocator_type(table_.node_alloc()));
       }
 
       insert_return_type insert(node_type&& np)
       {
         insert_return_type result;
         table_.move_insert_node_type_unique((node_type&)np, result);
         return result;
       }
 
       iterator insert(const_iterator hint, node_type&& np)
       {
         return table_.move_insert_node_type_with_hint_unique(hint, np);
       }
 
       template <class... Args>
       std::pair<iterator, bool> try_emplace(key_type const& k, Args&&... args)
       {
         return table_.try_emplace_unique(k, std::forward<Args>(args)...);
       }
 
       template <class... Args>
       std::pair<iterator, bool> try_emplace(key_type&& k, Args&&... args)
       {
         return table_.try_emplace_unique(
           std::move(k), std::forward<Args>(args)...);
       }
 
       template <class Key, class... Args>
       typename boost::enable_if_c<
         detail::transparent_non_iterable<Key, unordered_map>::value,
         std::pair<iterator, bool> >::type
       try_emplace(Key&& k, Args&&... args)
       {
         return table_.try_emplace_unique(
           std::forward<Key>(k), std::forward<Args>(args)...);
       }
 
       template <class... Args>
       iterator try_emplace(
         const_iterator hint, key_type const& k, Args&&... args)
       {
         return table_.try_emplace_hint_unique(
           hint, k, std::forward<Args>(args)...);
       }
 
       template <class... Args>
       iterator try_emplace(const_iterator hint, key_type&& k, Args&&... args)
       {
         return table_.try_emplace_hint_unique(
           hint, std::move(k), std::forward<Args>(args)...);
       }
 
       template <class Key, class... Args>
       typename boost::enable_if_c<
         detail::transparent_non_iterable<Key, unordered_map>::value,
         iterator>::type
       try_emplace(const_iterator hint, Key&& k, Args&&... args)
       {
         return table_.try_emplace_hint_unique(
           hint, std::forward<Key>(k), std::forward<Args>(args)...);
       }
 
       template <class M>
       std::pair<iterator, bool> insert_or_assign(key_type const& k, M&& obj)
       {
         return table_.insert_or_assign_unique(k, std::forward<M>(obj));
       }
 
       template <class M>
       std::pair<iterator, bool> insert_or_assign(key_type&& k, M&& obj)
       {
         return table_.insert_or_assign_unique(
           std::move(k), std::forward<M>(obj));
       }
 
       template <class Key, class M>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         std::pair<iterator, bool> >::type
       insert_or_assign(Key&& k, M&& obj)
       {
         return table_.insert_or_assign_unique(
           std::forward<Key>(k), std::forward<M>(obj));
       }
 
       template <class M>
       iterator insert_or_assign(const_iterator, key_type const& k, M&& obj)
       {
         return table_.insert_or_assign_unique(k, std::forward<M>(obj)).first;
       }
 
       template <class M>
       iterator insert_or_assign(const_iterator, key_type&& k, M&& obj)
       {
         return table_
           .insert_or_assign_unique(std::move(k), std::forward<M>(obj))
           .first;
       }
 
       template <class Key, class M>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         iterator>::type
       insert_or_assign(const_iterator, Key&& k, M&& obj)
       {
         return table_
           .insert_or_assign_unique(std::forward<Key>(k), std::forward<M>(obj))
           .first;
       }
 
       iterator erase(iterator);
       iterator erase(const_iterator);
       size_type erase(const key_type&);
       iterator erase(const_iterator, const_iterator);
 
       template <class Key>
       typename boost::enable_if_c<
         detail::transparent_non_iterable<Key, unordered_map>::value,
         size_type>::type
       erase(Key&& k)
       {
         return table_.erase_key_unique_impl(std::forward<Key>(k));
       }
 
       BOOST_UNORDERED_DEPRECATED("Use erase instead")
       void quick_erase(const_iterator it) { erase(it); }
       BOOST_UNORDERED_DEPRECATED("Use erase instead")
       void erase_return_void(const_iterator it) { erase(it); }
 
       void swap(unordered_map&)
         noexcept(value_allocator_traits::is_always_equal::value&&
             boost::unordered::detail::is_nothrow_swappable<H>::value&&
               boost::unordered::detail::is_nothrow_swappable<P>::value);
       void clear() noexcept { table_.clear_impl(); }
 
       template <typename H2, typename P2>
       void merge(boost::unordered_map<K, T, H2, P2, A>& source);
 
       template <typename H2, typename P2>
       void merge(boost::unordered_map<K, T, H2, P2, A>&& source);
 
       template <typename H2, typename P2>
       void merge(boost::unordered_multimap<K, T, H2, P2, A>& source);
 
       template <typename H2, typename P2>
       void merge(boost::unordered_multimap<K, T, H2, P2, A>&& source);
 
       // observers
 
       hasher hash_function() const;
       key_equal key_eq() const;
 
       // lookup
 
       iterator find(const key_type&);
       const_iterator find(const key_type&) const;
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         iterator>::type
       find(const Key& key)
       {
         return table_.find(key);
       }
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         const_iterator>::type
       find(const Key& key) const
       {
         return const_iterator(table_.find(key));
       }
 
       template <class CompatibleKey, class CompatibleHash,
         class CompatiblePredicate>
       iterator find(CompatibleKey const&, CompatibleHash const&,
         CompatiblePredicate const&);
 
       template <class CompatibleKey, class CompatibleHash,
         class CompatiblePredicate>
       const_iterator find(CompatibleKey const&, CompatibleHash const&,
         CompatiblePredicate const&) const;
 
       bool contains(const key_type& k) const
       {
         return table_.find(k) != this->end();
       }
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         bool>::type
       contains(const Key& k) const
       {
         return table_.find(k) != this->end();
       }
 
       size_type count(const key_type&) const;
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         size_type>::type
       count(const Key& k) const
       {
         return (table_.find(k) != this->end() ? 1 : 0);
       }
 
       std::pair<iterator, iterator> equal_range(const key_type&);
       std::pair<const_iterator, const_iterator> equal_range(
         const key_type&) const;
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         std::pair<iterator, iterator> >::type
       equal_range(const Key& key)
       {
         iterator first = table_.find(key);
         iterator last = first;
         if (last != this->end()) {
           ++last;
         }
 
         return std::make_pair(first, last);
       }
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         std::pair<const_iterator, const_iterator> >::type
       equal_range(const Key& key) const
       {
         iterator first = table_.find(key);
         iterator last = first;
         if (last != this->end()) {
           ++last;
         }
 
         return std::make_pair(first, last);
       }
 
       mapped_type& operator[](const key_type&);
       mapped_type& operator[](key_type&&);
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         mapped_type&>::type
       operator[](Key&& k);
 
       mapped_type& at(const key_type&);
       mapped_type const& at(const key_type&) const;
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         mapped_type&>::type
       at(Key&& k);
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         mapped_type const&>::type
       at(Key&& k) const;
 
       // bucket interface
 
       size_type bucket_count() const noexcept { return table_.bucket_count(); }
 
       size_type max_bucket_count() const noexcept
       {
         return table_.max_bucket_count();
       }
 
       size_type bucket_size(size_type) const;
 
       size_type bucket(const key_type& k) const
       {
         return table_.hash_to_bucket(table_.hash(k));
       }
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         size_type>::type
       bucket(Key&& k) const
       {
         return table_.hash_to_bucket(table_.hash(std::forward<Key>(k)));
       }
 
       local_iterator begin(size_type n) { return table_.begin(n); }
 
       const_local_iterator begin(size_type n) const
       {
         return const_local_iterator(table_.begin(n));
       }
 
       local_iterator end(size_type) { return local_iterator(); }
       const_local_iterator end(size_type) const
       {
         return const_local_iterator();
       }
 
       const_local_iterator cbegin(size_type n) const
       {
         return const_local_iterator(table_.begin(n));
       }
 
       const_local_iterator cend(size_type) const
       {
         return const_local_iterator();
       }
 
       // hash policy
 
       float load_factor() const noexcept;
       float max_load_factor() const noexcept { return table_.mlf_; }
       void max_load_factor(float) noexcept;
       void rehash(size_type);
       void reserve(size_type);
 
 #if !BOOST_WORKAROUND(BOOST_BORLANDC, < 0x0582)
       friend bool operator==
         <K, T, H, P, A>(unordered_map const&, unordered_map const&);
       friend bool operator!=
         <K, T, H, P, A>(unordered_map const&, unordered_map const&);
 #endif
     }; // class template unordered_map
 
     template <class Archive, class K, class T, class H, class P, class A>
     void serialize(
       Archive& ar, unordered_map<K, T, H, P, A>& m, unsigned int version)
     {
       detail::serialize_fca_container(ar, m, version);
     }
 
 #if BOOST_UNORDERED_TEMPLATE_DEDUCTION_GUIDES
 
     template <class InputIterator,
       class Hash =
         boost::hash<boost::unordered::detail::iter_key_t<InputIterator> >,
       class Pred =
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
       class Allocator = std::allocator<
         boost::unordered::detail::iter_to_alloc_t<InputIterator> >,
       class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
       class = std::enable_if_t<detail::is_hash_v<Hash> >,
       class = std::enable_if_t<detail::is_pred_v<Pred> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
       -> unordered_map<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>, Hash, Pred,
         Allocator>;
 
     template <class Key, class T,
       class Hash = boost::hash<std::remove_const_t<Key> >,
       class Pred = std::equal_to<std::remove_const_t<Key> >,
       class Allocator = std::allocator<std::pair<const Key, T> >,
       class = std::enable_if_t<detail::is_hash_v<Hash> >,
       class = std::enable_if_t<detail::is_pred_v<Pred> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(std::initializer_list<std::pair<Key, T> >,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
       -> unordered_map<std::remove_const_t<Key>, T, Hash, Pred, Allocator>;
 
     template <class InputIterator, class Allocator,
       class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(InputIterator, InputIterator, std::size_t, Allocator)
       -> unordered_map<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
         boost::hash<boost::unordered::detail::iter_key_t<InputIterator> >,
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
         Allocator>;
 
     template <class InputIterator, class Allocator,
       class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(InputIterator, InputIterator, Allocator)
       -> unordered_map<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
         boost::hash<boost::unordered::detail::iter_key_t<InputIterator> >,
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
       class = std::enable_if_t<detail::is_hash_v<Hash> >,
       class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> unordered_map<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>, Hash,
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
         Allocator>;
 
     template <class Key, class T, class Allocator,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Allocator) -> unordered_map<std::remove_const_t<Key>, T,
       boost::hash<std::remove_const_t<Key> >,
       std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Allocator,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(std::initializer_list<std::pair<Key, T> >, Allocator)
       -> unordered_map<std::remove_const_t<Key>, T,
         boost::hash<std::remove_const_t<Key> >,
         std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Hash, class Allocator,
       class = std::enable_if_t<detail::is_hash_v<Hash> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(std::initializer_list<std::pair<Key, T> >, std::size_t, Hash,
       Allocator) -> unordered_map<std::remove_const_t<Key>, T, Hash,
       std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
 #endif
 
     template <class K, class T, class H, class P, class A>
     class unordered_multimap
     {
       template <typename, typename, typename, typename, typename>
       friend class unordered_map;
 
     public:
       typedef K key_type;
       typedef T mapped_type;
       typedef std::pair<const K, T> value_type;
       typedef typename boost::unordered::detail::type_identity<H>::type hasher;
       typedef
         typename boost::unordered::detail::type_identity<P>::type key_equal;
       typedef typename boost::unordered::detail::type_identity<A>::type
         allocator_type;
 
     private:
       typedef boost::unordered::detail::map<A, K, T, H, P> types;
       typedef typename types::value_allocator_traits value_allocator_traits;
       typedef typename types::table table;
 
     public:
       typedef typename value_allocator_traits::pointer pointer;
       typedef typename value_allocator_traits::const_pointer const_pointer;
 
       typedef value_type& reference;
       typedef value_type const& const_reference;
 
       typedef std::size_t size_type;
       typedef std::ptrdiff_t difference_type;
 
       typedef typename table::iterator iterator;
       typedef typename table::c_iterator const_iterator;
       typedef typename table::l_iterator local_iterator;
       typedef typename table::cl_iterator const_local_iterator;
       typedef typename types::node_type node_type;
 
     private:
       table table_;
 
     public:
       // constructors
 
       unordered_multimap();
 
       explicit unordered_multimap(size_type, const hasher& = hasher(),
         const key_equal& = key_equal(),
         const allocator_type& = allocator_type());
 
       template <class InputIt>
       unordered_multimap(InputIt, InputIt,
         size_type = boost::unordered::detail::default_bucket_count,
         const hasher& = hasher(), const key_equal& = key_equal(),
         const allocator_type& = allocator_type());
 
       unordered_multimap(unordered_multimap const&);
 
       unordered_multimap(unordered_multimap&& other)
         noexcept(table::nothrow_move_constructible)
           : table_(other.table_, boost::unordered::detail::move_tag())
       {
         // The move is done in table_
       }
 
       explicit unordered_multimap(allocator_type const&);
 
       unordered_multimap(unordered_multimap const&, allocator_type const&);
 
       unordered_multimap(unordered_multimap&&, allocator_type const&);
 
       unordered_multimap(std::initializer_list<value_type>,
         size_type = boost::unordered::detail::default_bucket_count,
         const hasher& = hasher(), const key_equal& l = key_equal(),
         const allocator_type& = allocator_type());
 
       explicit unordered_multimap(size_type, const allocator_type&);
 
       explicit unordered_multimap(
         size_type, const hasher&, const allocator_type&);
 
       template <class InputIterator>
       unordered_multimap(InputIterator, InputIterator, const allocator_type&);
 
       template <class InputIt>
       unordered_multimap(InputIt, InputIt, size_type, const allocator_type&);
 
       template <class InputIt>
       unordered_multimap(
         InputIt, InputIt, size_type, const hasher&, const allocator_type&);
 
       unordered_multimap(
         std::initializer_list<value_type>, const allocator_type&);
 
       unordered_multimap(
         std::initializer_list<value_type>, size_type, const allocator_type&);
 
       unordered_multimap(std::initializer_list<value_type>, size_type,
         const hasher&, const allocator_type&);
 
       // Destructor
 
       ~unordered_multimap() noexcept;
 
       // Assign
 
       unordered_multimap& operator=(unordered_multimap const& x)
       {
         table_.assign(x.table_, std::false_type());
         return *this;
       }
 
       unordered_multimap& operator=(unordered_multimap&& x)
         noexcept(value_allocator_traits::is_always_equal::value&&
             std::is_nothrow_move_assignable<H>::value&&
               std::is_nothrow_move_assignable<P>::value)
       {
         table_.move_assign(x.table_, std::false_type());
         return *this;
       }
 
       unordered_multimap& operator=(std::initializer_list<value_type>);
 
       allocator_type get_allocator() const noexcept
       {
         return allocator_type(table_.node_alloc());
       }
 
       // iterators
 
       iterator begin() noexcept { return iterator(table_.begin()); }
 
       const_iterator begin() const noexcept
       {
         return const_iterator(table_.begin());
       }
 
       iterator end() noexcept { return iterator(); }
 
       const_iterator end() const noexcept { return const_iterator(); }
 
       const_iterator cbegin() const noexcept
       {
         return const_iterator(table_.begin());
       }
 
       const_iterator cend() const noexcept { return const_iterator(); }
 
       // size and capacity
 
       BOOST_ATTRIBUTE_NODISCARD bool empty() const noexcept
       {
         return table_.size_ == 0;
       }
 
       size_type size() const noexcept { return table_.size_; }
 
       size_type max_size() const noexcept;
 
       // emplace
 
       template <class... Args> iterator emplace(Args&&... args)
       {
         return iterator(table_.emplace_equiv(
           boost::unordered::detail::func::construct_node_from_args(
             table_.node_alloc(), std::forward<Args>(args)...)));
       }
 
       template <class... Args>
       iterator emplace_hint(const_iterator hint, Args&&... args)
       {
         return iterator(table_.emplace_hint_equiv(
           hint, boost::unordered::detail::func::construct_node_from_args(
                   table_.node_alloc(), std::forward<Args>(args)...)));
       }
 
       iterator insert(value_type const& x) { return this->emplace(x); }
 
       iterator insert(value_type&& x) { return this->emplace(std::move(x)); }
 
       template <class P2>
       typename boost::enable_if<std::is_constructible<value_type, P2&&>,
         iterator>::type
       insert(P2&& obj)
       {
         return this->emplace(std::forward<P2>(obj));
       }
 
       iterator insert(const_iterator hint, value_type const& x)
       {
         return this->emplace_hint(hint, x);
       }
 
       iterator insert(const_iterator hint, value_type&& x)
       {
         return this->emplace_hint(hint, std::move(x));
       }
 
       template <class P2>
       typename boost::enable_if<std::is_constructible<value_type, P2&&>,
         iterator>::type
       insert(const_iterator hint, P2&& obj)
       {
         return this->emplace_hint(hint, std::forward<P2>(obj));
       }
 
       template <class InputIt> void insert(InputIt, InputIt);
 
       void insert(std::initializer_list<value_type>);
 
       // extract
 
       node_type extract(const_iterator position)
       {
         return node_type(
           table_.extract_by_iterator_equiv(position), table_.node_alloc());
       }
 
       node_type extract(const key_type& k)
       {
         return node_type(table_.extract_by_key_impl(k), table_.node_alloc());
       }
 
       template <class Key>
       typename boost::enable_if_c<
         detail::transparent_non_iterable<Key, unordered_multimap>::value,
         node_type>::type
       extract(const Key& k)
       {
         return node_type(table_.extract_by_key_impl(k), table_.node_alloc());
       }
 
       iterator insert(node_type&& np)
       {
         return table_.move_insert_node_type_equiv(np);
       }
 
       iterator insert(const_iterator hint, node_type&& np)
       {
         return table_.move_insert_node_type_with_hint_equiv(hint, np);
       }
 
       iterator erase(iterator);
       iterator erase(const_iterator);
       size_type erase(const key_type&);
       iterator erase(const_iterator, const_iterator);
 
       template <class Key>
       typename boost::enable_if_c<
         detail::transparent_non_iterable<Key, unordered_multimap>::value,
         size_type>::type
       erase(Key&& k)
       {
         return table_.erase_key_equiv_impl(std::forward<Key>(k));
       }
 
       BOOST_UNORDERED_DEPRECATED("Use erase instead")
       void quick_erase(const_iterator it) { erase(it); }
       BOOST_UNORDERED_DEPRECATED("Use erase instead")
       void erase_return_void(const_iterator it) { erase(it); }
 
       void swap(unordered_multimap&)
         noexcept(value_allocator_traits::is_always_equal::value&&
             boost::unordered::detail::is_nothrow_swappable<H>::value&&
               boost::unordered::detail::is_nothrow_swappable<P>::value);
       void clear() noexcept { table_.clear_impl(); }
 
       template <typename H2, typename P2>
       void merge(boost::unordered_multimap<K, T, H2, P2, A>& source);
 
       template <typename H2, typename P2>
       void merge(boost::unordered_multimap<K, T, H2, P2, A>&& source);
 
       template <typename H2, typename P2>
       void merge(boost::unordered_map<K, T, H2, P2, A>& source);
 
       template <typename H2, typename P2>
       void merge(boost::unordered_map<K, T, H2, P2, A>&& source);
 
       // observers
 
       hasher hash_function() const;
       key_equal key_eq() const;
 
       // lookup
 
       iterator find(const key_type&);
       const_iterator find(const key_type&) const;
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         iterator>::type
       find(const Key& key)
       {
         return table_.find(key);
       }
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         const_iterator>::type
       find(const Key& key) const
       {
         return const_iterator(table_.find(key));
       }
 
       template <class CompatibleKey, class CompatibleHash,
         class CompatiblePredicate>
       iterator find(CompatibleKey const&, CompatibleHash const&,
         CompatiblePredicate const&);
 
       template <class CompatibleKey, class CompatibleHash,
         class CompatiblePredicate>
       const_iterator find(CompatibleKey const&, CompatibleHash const&,
         CompatiblePredicate const&) const;
 
       bool contains(key_type const& k) const
       {
         return table_.find(k) != this->end();
       }
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         bool>::type
       contains(const Key& k) const
       {
         return table_.find(k) != this->end();
       }
 
       size_type count(const key_type&) const;
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         size_type>::type
       count(const Key& k) const
       {
         return table_.group_count(k);
       }
 
       std::pair<iterator, iterator> equal_range(const key_type&);
       std::pair<const_iterator, const_iterator> equal_range(
         const key_type&) const;
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         std::pair<iterator, iterator> >::type
       equal_range(const Key& key)
       {
         iterator p = table_.find(key);
         return std::make_pair(p, table_.next_group(key, p));
       }
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         std::pair<const_iterator, const_iterator> >::type
       equal_range(const Key& key) const
       {
         iterator p = table_.find(key);
         return std::make_pair(
           const_iterator(p), const_iterator(table_.next_group(key, p)));
       }
 
       // bucket interface
 
       size_type bucket_count() const noexcept { return table_.bucket_count(); }
 
       size_type max_bucket_count() const noexcept
       {
         return table_.max_bucket_count();
       }
 
       size_type bucket_size(size_type) const;
 
       size_type bucket(const key_type& k) const
       {
         return table_.hash_to_bucket(table_.hash(k));
       }
 
       template <class Key>
       typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
         size_type>::type
       bucket(Key&& k) const
       {
         return table_.hash_to_bucket(table_.hash(std::forward<Key>(k)));
       }
 
       local_iterator begin(size_type n)
       {
         return local_iterator(table_.begin(n));
       }
 
       const_local_iterator begin(size_type n) const
       {
         return const_local_iterator(table_.begin(n));
       }
 
       local_iterator end(size_type) { return local_iterator(); }
 
       const_local_iterator end(size_type) const
       {
         return const_local_iterator();
       }
 
       const_local_iterator cbegin(size_type n) const
       {
         return const_local_iterator(table_.begin(n));
       }
 
       const_local_iterator cend(size_type) const
       {
         return const_local_iterator();
       }
 
       // hash policy
 
       float load_factor() const noexcept;
       float max_load_factor() const noexcept { return table_.mlf_; }
       void max_load_factor(float) noexcept;
       void rehash(size_type);
       void reserve(size_type);
 
 #if !BOOST_WORKAROUND(BOOST_BORLANDC, < 0x0582)
       friend bool operator==
         <K, T, H, P, A>(unordered_multimap const&, unordered_multimap const&);
       friend bool operator!=
         <K, T, H, P, A>(unordered_multimap const&, unordered_multimap const&);
 #endif
     }; // class template unordered_multimap
 
     template <class Archive, class K, class T, class H, class P, class A>
     void serialize(
       Archive& ar, unordered_multimap<K, T, H, P, A>& m, unsigned int version)
     {
       detail::serialize_fca_container(ar, m, version);
     }
 
 #if BOOST_UNORDERED_TEMPLATE_DEDUCTION_GUIDES
 
     template <class InputIterator,
       class Hash =
         boost::hash<boost::unordered::detail::iter_key_t<InputIterator> >,
       class Pred =
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
       class Allocator = std::allocator<
         boost::unordered::detail::iter_to_alloc_t<InputIterator> >,
       class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
       class = std::enable_if_t<detail::is_hash_v<Hash> >,
       class = std::enable_if_t<detail::is_pred_v<Pred> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
       -> unordered_multimap<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>, Hash, Pred,
         Allocator>;
 
     template <class Key, class T,
       class Hash = boost::hash<std::remove_const_t<Key> >,
       class Pred = std::equal_to<std::remove_const_t<Key> >,
       class Allocator = std::allocator<std::pair<const Key, T> >,
       class = std::enable_if_t<detail::is_hash_v<Hash> >,
       class = std::enable_if_t<detail::is_pred_v<Pred> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(std::initializer_list<std::pair<Key, T> >,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
       -> unordered_multimap<std::remove_const_t<Key>, T, Hash, Pred, Allocator>;
 
     template <class InputIterator, class Allocator,
       class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(InputIterator, InputIterator, std::size_t, Allocator)
       -> unordered_multimap<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
         boost::hash<boost::unordered::detail::iter_key_t<InputIterator> >,
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
         Allocator>;
 
     template <class InputIterator, class Allocator,
       class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(InputIterator, InputIterator, Allocator)
       -> unordered_multimap<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
         boost::hash<boost::unordered::detail::iter_key_t<InputIterator> >,
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
       class = std::enable_if_t<detail::is_hash_v<Hash> >,
       class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(
       InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> unordered_multimap<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>, Hash,
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
         Allocator>;
 
     template <class Key, class T, class Allocator,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Allocator) -> unordered_multimap<std::remove_const_t<Key>, T,
       boost::hash<std::remove_const_t<Key> >,
       std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Allocator,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(std::initializer_list<std::pair<Key, T> >, Allocator)
       -> unordered_multimap<std::remove_const_t<Key>, T,
         boost::hash<std::remove_const_t<Key> >,
         std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Hash, class Allocator,
       class = std::enable_if_t<detail::is_hash_v<Hash> >,
       class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Hash, Allocator) -> unordered_multimap<std::remove_const_t<Key>, T, Hash,
       std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
 #endif
 
     ////////////////////////////////////////////////////////////////////////////
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map()
     {
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map(size_type n, const hasher& hf,
       const key_equal& eql, const allocator_type& a)
         : table_(n, hf, eql, a)
     {
     }
 
     template <class K, class T, class H, class P, class A>
     template <class InputIt>
     unordered_map<K, T, H, P, A>::unordered_map(InputIt f, InputIt l,
       size_type n, const hasher& hf, const key_equal& eql,
       const allocator_type& a)
         : table_(boost::unordered::detail::initial_size(f, l, n), hf, eql, a)
     {
       this->insert(f, l);
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map(unordered_map const& other)
         : table_(other.table_,
             unordered_map::value_allocator_traits::
               select_on_container_copy_construction(other.get_allocator()))
     {
       if (other.size()) {
         table_.copy_buckets(other.table_, std::true_type());
       }
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map(allocator_type const& a)
         : table_(boost::unordered::detail::default_bucket_count, hasher(),
             key_equal(), a)
     {
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map(
       unordered_map const& other, allocator_type const& a)
         : table_(other.table_, a)
     {
       if (other.table_.size_) {
         table_.copy_buckets(other.table_, std::true_type());
       }
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map(
       unordered_map&& other, allocator_type const& a)
         : table_(other.table_, a, boost::unordered::detail::move_tag())
     {
       table_.move_construct_buckets(other.table_);
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map(
       std::initializer_list<value_type> list, size_type n, const hasher& hf,
       const key_equal& eql, const allocator_type& a)
         : table_(
             boost::unordered::detail::initial_size(list.begin(), list.end(), n),
             hf, eql, a)
     {
       this->insert(list.begin(), list.end());
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map(
       size_type n, const allocator_type& a)
         : table_(n, hasher(), key_equal(), a)
     {
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map(
       size_type n, const hasher& hf, const allocator_type& a)
         : table_(n, hf, key_equal(), a)
     {
     }
 
     template <class K, class T, class H, class P, class A>
     template <class InputIterator>
     unordered_map<K, T, H, P, A>::unordered_map(
       InputIterator f, InputIterator l, const allocator_type& a)
         : table_(boost::unordered::detail::initial_size(
                    f, l, detail::default_bucket_count),
             hasher(), key_equal(), a)
     {
       this->insert(f, l);
     }
 
     template <class K, class T, class H, class P, class A>
     template <class InputIt>
     unordered_map<K, T, H, P, A>::unordered_map(
       InputIt f, InputIt l, size_type n, const allocator_type& a)
         : table_(boost::unordered::detail::initial_size(f, l, n), hasher(),
             key_equal(), a)
     {
       this->insert(f, l);
     }
 
     template <class K, class T, class H, class P, class A>
     template <class InputIt>
     unordered_map<K, T, H, P, A>::unordered_map(InputIt f, InputIt l,
       size_type n, const hasher& hf, const allocator_type& a)
         : table_(
             boost::unordered::detail::initial_size(f, l, n), hf, key_equal(), a)
     {
       this->insert(f, l);
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map(
       std::initializer_list<value_type> list, const allocator_type& a)
         : table_(boost::unordered::detail::initial_size(
                    list.begin(), list.end(), detail::default_bucket_count),
             hasher(), key_equal(), a)
     {
       this->insert(list.begin(), list.end());
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map(
       std::initializer_list<value_type> list, size_type n,
       const allocator_type& a)
         : table_(
             boost::unordered::detail::initial_size(list.begin(), list.end(), n),
             hasher(), key_equal(), a)
     {
       this->insert(list.begin(), list.end());
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::unordered_map(
       std::initializer_list<value_type> list, size_type n, const hasher& hf,
       const allocator_type& a)
         : table_(
             boost::unordered::detail::initial_size(list.begin(), list.end(), n),
             hf, key_equal(), a)
     {
       this->insert(list.begin(), list.end());
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>::~unordered_map() noexcept
     {
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_map<K, T, H, P, A>& unordered_map<K, T, H, P, A>::operator=(
       std::initializer_list<value_type> list)
     {
       this->clear();
       this->insert(list.begin(), list.end());
       return *this;
     }
 
     // size and capacity
 
     template <class K, class T, class H, class P, class A>
     std::size_t unordered_map<K, T, H, P, A>::max_size() const noexcept
     {
       using namespace std;
 
       // size <= mlf_ * count
       return boost::unordered::detail::double_to_size(
                ceil(static_cast<double>(table_.mlf_) *
                     static_cast<double>(table_.max_bucket_count()))) -
              1;
     }
 
     // modifiers
 
     template <class K, class T, class H, class P, class A>
     template <class InputIt>
     void unordered_map<K, T, H, P, A>::insert(InputIt first, InputIt last)
     {
       if (first != last) {
         table_.insert_range_unique(
           table::extractor::extract(*first), first, last);
       }
     }
 
     template <class K, class T, class H, class P, class A>
     void unordered_map<K, T, H, P, A>::insert(
       std::initializer_list<value_type> list)
     {
       this->insert(list.begin(), list.end());
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::iterator
     unordered_map<K, T, H, P, A>::erase(iterator position)
     {
       return table_.erase_node(position);
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::iterator
     unordered_map<K, T, H, P, A>::erase(const_iterator position)
     {
       return table_.erase_node(position);
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::size_type
     unordered_map<K, T, H, P, A>::erase(const key_type& k)
     {
       return table_.erase_key_unique_impl(k);
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::iterator
     unordered_map<K, T, H, P, A>::erase(
       const_iterator first, const_iterator last)
     {
       return table_.erase_nodes_range(first, last);
     }
 
     template <class K, class T, class H, class P, class A>
     void unordered_map<K, T, H, P, A>::swap(unordered_map& other)
       noexcept(value_allocator_traits::is_always_equal::value&&
           boost::unordered::detail::is_nothrow_swappable<H>::value&&
             boost::unordered::detail::is_nothrow_swappable<P>::value)
     {
       table_.swap(other.table_);
     }
 
     template <class K, class T, class H, class P, class A>
     template <typename H2, typename P2>
     void unordered_map<K, T, H, P, A>::merge(
       boost::unordered_map<K, T, H2, P2, A>& source)
     {
       table_.merge_unique(source.table_);
     }
 
     template <class K, class T, class H, class P, class A>
     template <typename H2, typename P2>
     void unordered_map<K, T, H, P, A>::merge(
       boost::unordered_map<K, T, H2, P2, A>&& source)
     {
       table_.merge_unique(source.table_);
     }
 
     template <class K, class T, class H, class P, class A>
     template <typename H2, typename P2>
     void unordered_map<K, T, H, P, A>::merge(
       boost::unordered_multimap<K, T, H2, P2, A>& source)
     {
       table_.merge_unique(source.table_);
     }
 
     template <class K, class T, class H, class P, class A>
     template <typename H2, typename P2>
     void unordered_map<K, T, H, P, A>::merge(
       boost::unordered_multimap<K, T, H2, P2, A>&& source)
     {
       table_.merge_unique(source.table_);
     }
 
     // observers
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::hasher
     unordered_map<K, T, H, P, A>::hash_function() const
     {
       return table_.hash_function();
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::key_equal
     unordered_map<K, T, H, P, A>::key_eq() const
     {
       return table_.key_eq();
     }
 
     // lookup
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::iterator
     unordered_map<K, T, H, P, A>::find(const key_type& k)
     {
       return iterator(table_.find(k));
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::const_iterator
     unordered_map<K, T, H, P, A>::find(const key_type& k) const
     {
       return const_iterator(table_.find(k));
     }
 
     template <class K, class T, class H, class P, class A>
     template <class CompatibleKey, class CompatibleHash,
       class CompatiblePredicate>
     typename unordered_map<K, T, H, P, A>::iterator
     unordered_map<K, T, H, P, A>::find(CompatibleKey const& k,
       CompatibleHash const& hash, CompatiblePredicate const& eq)
     {
       return table_.transparent_find(k, hash, eq);
     }
 
     template <class K, class T, class H, class P, class A>
     template <class CompatibleKey, class CompatibleHash,
       class CompatiblePredicate>
     typename unordered_map<K, T, H, P, A>::const_iterator
     unordered_map<K, T, H, P, A>::find(CompatibleKey const& k,
       CompatibleHash const& hash, CompatiblePredicate const& eq) const
     {
       return table_.transparent_find(k, hash, eq);
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::size_type
     unordered_map<K, T, H, P, A>::count(const key_type& k) const
     {
       return table_.find_node(k) ? 1 : 0;
     }
 
     template <class K, class T, class H, class P, class A>
     std::pair<typename unordered_map<K, T, H, P, A>::iterator,
       typename unordered_map<K, T, H, P, A>::iterator>
     unordered_map<K, T, H, P, A>::equal_range(const key_type& k)
     {
       iterator first = table_.find(k);
       iterator second = first;
       if (second != this->end()) {
         ++second;
       }
       return std::make_pair(first, second);
     }
 
     template <class K, class T, class H, class P, class A>
     std::pair<typename unordered_map<K, T, H, P, A>::const_iterator,
       typename unordered_map<K, T, H, P, A>::const_iterator>
     unordered_map<K, T, H, P, A>::equal_range(const key_type& k) const
     {
       iterator first = table_.find(k);
       iterator second = first;
       if (second != this->end()) {
         ++second;
       }
       return std::make_pair(const_iterator(first), const_iterator(second));
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::mapped_type&
     unordered_map<K, T, H, P, A>::operator[](const key_type& k)
     {
       return table_.try_emplace_unique(k).first->second;
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::mapped_type&
     unordered_map<K, T, H, P, A>::operator[](key_type&& k)
     {
       return table_.try_emplace_unique(std::move(k)).first->second;
     }
 
     template <class K, class T, class H, class P, class A>
     template <class Key>
     typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
       typename unordered_map<K, T, H, P, A>::mapped_type&>::type
     unordered_map<K, T, H, P, A>::operator[](Key&& k)
     {
       return table_.try_emplace_unique(std::forward<Key>(k)).first->second;
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::mapped_type&
     unordered_map<K, T, H, P, A>::at(const key_type& k)
     {
       typedef typename table::node_pointer node_pointer;
 
       if (table_.size_) {
         node_pointer p = table_.find_node(k);
         if (p)
           return p->value().second;
       }
 
       boost::unordered::detail::throw_out_of_range(
         "Unable to find key in unordered_map.");
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::mapped_type const&
     unordered_map<K, T, H, P, A>::at(const key_type& k) const
     {
       typedef typename table::node_pointer node_pointer;
 
       if (table_.size_) {
         node_pointer p = table_.find_node(k);
         if (p)
           return p->value().second;
       }
 
       boost::unordered::detail::throw_out_of_range(
         "Unable to find key in unordered_map.");
     }
 
     template <class K, class T, class H, class P, class A>
     template <class Key>
     typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
       typename unordered_map<K, T, H, P, A>::mapped_type&>::type
     unordered_map<K, T, H, P, A>::at(Key&& k)
     {
       typedef typename table::node_pointer node_pointer;
 
       if (table_.size_) {
         node_pointer p = table_.find_node(std::forward<Key>(k));
         if (p)
           return p->value().second;
       }
 
       boost::unordered::detail::throw_out_of_range(
         "Unable to find key in unordered_map.");
     }
 
     template <class K, class T, class H, class P, class A>
     template <class Key>
     typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
       typename unordered_map<K, T, H, P, A>::mapped_type const&>::type
     unordered_map<K, T, H, P, A>::at(Key&& k) const
     {
       typedef typename table::node_pointer node_pointer;
 
       if (table_.size_) {
         node_pointer p = table_.find_node(std::forward<Key>(k));
         if (p)
           return p->value().second;
       }
 
       boost::unordered::detail::throw_out_of_range(
         "Unable to find key in unordered_map.");
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_map<K, T, H, P, A>::size_type
     unordered_map<K, T, H, P, A>::bucket_size(size_type n) const
     {
       return table_.bucket_size(n);
     }
 
     // hash policy
 
     template <class K, class T, class H, class P, class A>
     float unordered_map<K, T, H, P, A>::load_factor() const noexcept
     {
       if (table_.size_ == 0) {
         return 0.0f;
       }
 
       BOOST_ASSERT(table_.bucket_count() != 0);
       return static_cast<float>(table_.size_) /
              static_cast<float>(table_.bucket_count());
     }
 
     template <class K, class T, class H, class P, class A>
     void unordered_map<K, T, H, P, A>::max_load_factor(float m) noexcept
     {
       table_.max_load_factor(m);
     }
 
     template <class K, class T, class H, class P, class A>
     void unordered_map<K, T, H, P, A>::rehash(size_type n)
     {
       table_.rehash(n);
     }
 
     template <class K, class T, class H, class P, class A>
     void unordered_map<K, T, H, P, A>::reserve(size_type n)
     {
       table_.reserve(n);
     }
 
     template <class K, class T, class H, class P, class A>
     inline bool operator==(unordered_map<K, T, H, P, A> const& m1,
       unordered_map<K, T, H, P, A> const& m2)
     {
 #if BOOST_WORKAROUND(BOOST_CODEGEARC, BOOST_TESTED_AT(0x0613))
       struct dummy
       {
         unordered_map<K, T, H, P, A> x;
       };
 #endif
       return m1.table_.equals_unique(m2.table_);
     }
 
     template <class K, class T, class H, class P, class A>
     inline bool operator!=(unordered_map<K, T, H, P, A> const& m1,
       unordered_map<K, T, H, P, A> const& m2)
     {
 #if BOOST_WORKAROUND(BOOST_CODEGEARC, BOOST_TESTED_AT(0x0613))
       struct dummy
       {
         unordered_map<K, T, H, P, A> x;
       };
 #endif
       return !m1.table_.equals_unique(m2.table_);
     }
 
     template <class K, class T, class H, class P, class A>
     inline void swap(unordered_map<K, T, H, P, A>& m1,
       unordered_map<K, T, H, P, A>& m2) noexcept(noexcept(m1.swap(m2)))
     {
 #if BOOST_WORKAROUND(BOOST_CODEGEARC, BOOST_TESTED_AT(0x0613))
       struct dummy
       {
         unordered_map<K, T, H, P, A> x;
       };
 #endif
       m1.swap(m2);
     }
 
     template <class K, class T, class H, class P, class A, class Predicate>
     typename unordered_map<K, T, H, P, A>::size_type erase_if(
       unordered_map<K, T, H, P, A>& c, Predicate pred)
     {
       return detail::erase_if(c, pred);
     }
 
     ////////////////////////////////////////////////////////////////////////////
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap()
     {
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(size_type n,
       const hasher& hf, const key_equal& eql, const allocator_type& a)
         : table_(n, hf, eql, a)
     {
     }
 
     template <class K, class T, class H, class P, class A>
     template <class InputIt>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(InputIt f, InputIt l,
       size_type n, const hasher& hf, const key_equal& eql,
       const allocator_type& a)
         : table_(boost::unordered::detail::initial_size(f, l, n), hf, eql, a)
     {
       this->insert(f, l);
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       unordered_multimap const& other)
         : table_(other.table_,
             unordered_multimap::value_allocator_traits::
               select_on_container_copy_construction(other.get_allocator()))
     {
       if (other.table_.size_) {
         table_.copy_buckets(other.table_, std::false_type());
       }
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       allocator_type const& a)
         : table_(boost::unordered::detail::default_bucket_count, hasher(),
             key_equal(), a)
     {
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       unordered_multimap const& other, allocator_type const& a)
         : table_(other.table_, a)
     {
       if (other.table_.size_) {
         table_.copy_buckets(other.table_, std::false_type());
       }
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       unordered_multimap&& other, allocator_type const& a)
         : table_(other.table_, a, boost::unordered::detail::move_tag())
     {
       table_.move_construct_buckets(other.table_);
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       std::initializer_list<value_type> list, size_type n, const hasher& hf,
       const key_equal& eql, const allocator_type& a)
         : table_(
             boost::unordered::detail::initial_size(list.begin(), list.end(), n),
             hf, eql, a)
     {
       this->insert(list.begin(), list.end());
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       size_type n, const allocator_type& a)
         : table_(n, hasher(), key_equal(), a)
     {
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       size_type n, const hasher& hf, const allocator_type& a)
         : table_(n, hf, key_equal(), a)
     {
     }
 
     template <class K, class T, class H, class P, class A>
     template <class InputIterator>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       InputIterator f, InputIterator l, const allocator_type& a)
         : table_(boost::unordered::detail::initial_size(
                    f, l, detail::default_bucket_count),
             hasher(), key_equal(), a)
     {
       this->insert(f, l);
     }
 
     template <class K, class T, class H, class P, class A>
     template <class InputIt>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       InputIt f, InputIt l, size_type n, const allocator_type& a)
         : table_(boost::unordered::detail::initial_size(f, l, n), hasher(),
             key_equal(), a)
     {
       this->insert(f, l);
     }
 
     template <class K, class T, class H, class P, class A>
     template <class InputIt>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(InputIt f, InputIt l,
       size_type n, const hasher& hf, const allocator_type& a)
         : table_(
             boost::unordered::detail::initial_size(f, l, n), hf, key_equal(), a)
     {
       this->insert(f, l);
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       std::initializer_list<value_type> list, const allocator_type& a)
         : table_(boost::unordered::detail::initial_size(
                    list.begin(), list.end(), detail::default_bucket_count),
             hasher(), key_equal(), a)
     {
       this->insert(list.begin(), list.end());
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       std::initializer_list<value_type> list, size_type n,
       const allocator_type& a)
         : table_(
             boost::unordered::detail::initial_size(list.begin(), list.end(), n),
             hasher(), key_equal(), a)
     {
       this->insert(list.begin(), list.end());
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::unordered_multimap(
       std::initializer_list<value_type> list, size_type n, const hasher& hf,
       const allocator_type& a)
         : table_(
             boost::unordered::detail::initial_size(list.begin(), list.end(), n),
             hf, key_equal(), a)
     {
       this->insert(list.begin(), list.end());
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>::~unordered_multimap() noexcept
     {
     }
 
     template <class K, class T, class H, class P, class A>
     unordered_multimap<K, T, H, P, A>&
     unordered_multimap<K, T, H, P, A>::operator=(
       std::initializer_list<value_type> list)
     {
       this->clear();
       this->insert(list.begin(), list.end());
       return *this;
     }
 
     // size and capacity
 
     template <class K, class T, class H, class P, class A>
     std::size_t unordered_multimap<K, T, H, P, A>::max_size() const noexcept
     {
       using namespace std;
 
       // size <= mlf_ * count
       return boost::unordered::detail::double_to_size(
                ceil(static_cast<double>(table_.mlf_) *
                     static_cast<double>(table_.max_bucket_count()))) -
              1;
     }
 
     // modifiers
 
     template <class K, class T, class H, class P, class A>
     template <class InputIt>
     void unordered_multimap<K, T, H, P, A>::insert(InputIt first, InputIt last)
     {
       table_.insert_range_equiv(first, last);
     }
 
     template <class K, class T, class H, class P, class A>
     void unordered_multimap<K, T, H, P, A>::insert(
       std::initializer_list<value_type> list)
     {
       this->insert(list.begin(), list.end());
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_multimap<K, T, H, P, A>::iterator
     unordered_multimap<K, T, H, P, A>::erase(iterator position)
     {
       BOOST_ASSERT(position != this->end());
       return table_.erase_node(position);
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_multimap<K, T, H, P, A>::iterator
     unordered_multimap<K, T, H, P, A>::erase(const_iterator position)
     {
       BOOST_ASSERT(position != this->end());
       return table_.erase_node(position);
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_multimap<K, T, H, P, A>::size_type
     unordered_multimap<K, T, H, P, A>::erase(const key_type& k)
     {
       return table_.erase_key_equiv(k);
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_multimap<K, T, H, P, A>::iterator
     unordered_multimap<K, T, H, P, A>::erase(
       const_iterator first, const_iterator last)
     {
       return table_.erase_nodes_range(first, last);
     }
 
     template <class K, class T, class H, class P, class A>
     void unordered_multimap<K, T, H, P, A>::swap(unordered_multimap& other)
       noexcept(value_allocator_traits::is_always_equal::value&&
           boost::unordered::detail::is_nothrow_swappable<H>::value&&
             boost::unordered::detail::is_nothrow_swappable<P>::value)
     {
       table_.swap(other.table_);
     }
 
     // observers
 
     template <class K, class T, class H, class P, class A>
     typename unordered_multimap<K, T, H, P, A>::hasher
     unordered_multimap<K, T, H, P, A>::hash_function() const
     {
       return table_.hash_function();
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_multimap<K, T, H, P, A>::key_equal
     unordered_multimap<K, T, H, P, A>::key_eq() const
     {
       return table_.key_eq();
     }
 
     template <class K, class T, class H, class P, class A>
     template <typename H2, typename P2>
     void unordered_multimap<K, T, H, P, A>::merge(
       boost::unordered_multimap<K, T, H2, P2, A>& source)
     {
       while (!source.empty()) {
         insert(source.extract(source.begin()));
       }
     }
 
     template <class K, class T, class H, class P, class A>
     template <typename H2, typename P2>
     void unordered_multimap<K, T, H, P, A>::merge(
       boost::unordered_multimap<K, T, H2, P2, A>&& source)
     {
       while (!source.empty()) {
         insert(source.extract(source.begin()));
       }
     }
 
     template <class K, class T, class H, class P, class A>
     template <typename H2, typename P2>
     void unordered_multimap<K, T, H, P, A>::merge(
       boost::unordered_map<K, T, H2, P2, A>& source)
     {
       while (!source.empty()) {
         insert(source.extract(source.begin()));
       }
     }
 
     template <class K, class T, class H, class P, class A>
     template <typename H2, typename P2>
     void unordered_multimap<K, T, H, P, A>::merge(
       boost::unordered_map<K, T, H2, P2, A>&& source)
     {
       while (!source.empty()) {
         insert(source.extract(source.begin()));
       }
     }
 
     // lookup
 
     template <class K, class T, class H, class P, class A>
     typename unordered_multimap<K, T, H, P, A>::iterator
     unordered_multimap<K, T, H, P, A>::find(const key_type& k)
     {
       return iterator(table_.find(k));
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_multimap<K, T, H, P, A>::const_iterator
     unordered_multimap<K, T, H, P, A>::find(const key_type& k) const
     {
       return const_iterator(table_.find(k));
     }
 
     template <class K, class T, class H, class P, class A>
     template <class CompatibleKey, class CompatibleHash,
       class CompatiblePredicate>
     typename unordered_multimap<K, T, H, P, A>::iterator
     unordered_multimap<K, T, H, P, A>::find(CompatibleKey const& k,
       CompatibleHash const& hash, CompatiblePredicate const& eq)
     {
       return table_.transparent_find(k, hash, eq);
     }
 
     template <class K, class T, class H, class P, class A>
     template <class CompatibleKey, class CompatibleHash,
       class CompatiblePredicate>
     typename unordered_multimap<K, T, H, P, A>::const_iterator
     unordered_multimap<K, T, H, P, A>::find(CompatibleKey const& k,
       CompatibleHash const& hash, CompatiblePredicate const& eq) const
     {
       return table_.transparent_find(k, hash, eq);
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_multimap<K, T, H, P, A>::size_type
     unordered_multimap<K, T, H, P, A>::count(const key_type& k) const
     {
       return table_.group_count(k);
     }
 
     template <class K, class T, class H, class P, class A>
     std::pair<typename unordered_multimap<K, T, H, P, A>::iterator,
       typename unordered_multimap<K, T, H, P, A>::iterator>
     unordered_multimap<K, T, H, P, A>::equal_range(const key_type& k)
     {
       iterator n = table_.find(k);
       return std::make_pair(n, (n == end() ? n : table_.next_group(k, n)));
     }
 
     template <class K, class T, class H, class P, class A>
     std::pair<typename unordered_multimap<K, T, H, P, A>::const_iterator,
       typename unordered_multimap<K, T, H, P, A>::const_iterator>
     unordered_multimap<K, T, H, P, A>::equal_range(const key_type& k) const
     {
       iterator n = table_.find(k);
       return std::make_pair(const_iterator(n),
         const_iterator(n == end() ? n : table_.next_group(k, n)));
     }
 
     template <class K, class T, class H, class P, class A>
     typename unordered_multimap<K, T, H, P, A>::size_type
     unordered_multimap<K, T, H, P, A>::bucket_size(size_type n) const
     {
       return table_.bucket_size(n);
     }
 
     // hash policy
 
     template <class K, class T, class H, class P, class A>
     float unordered_multimap<K, T, H, P, A>::load_factor() const noexcept
     {
       if (table_.size_ == 0) {
         return 0.0f;
       }
 
       BOOST_ASSERT(table_.bucket_count() != 0);
       return static_cast<float>(table_.size_) /
              static_cast<float>(table_.bucket_count());
     }
 
     template <class K, class T, class H, class P, class A>
     void unordered_multimap<K, T, H, P, A>::max_load_factor(float m) noexcept
     {
       table_.max_load_factor(m);
     }
 
     template <class K, class T, class H, class P, class A>
     void unordered_multimap<K, T, H, P, A>::rehash(size_type n)
     {
       table_.rehash(n);
     }
 
     template <class K, class T, class H, class P, class A>
     void unordered_multimap<K, T, H, P, A>::reserve(size_type n)
     {
       table_.reserve(n);
     }
 
     template <class K, class T, class H, class P, class A>
     inline bool operator==(unordered_multimap<K, T, H, P, A> const& m1,
       unordered_multimap<K, T, H, P, A> const& m2)
     {
 #if BOOST_WORKAROUND(BOOST_CODEGEARC, BOOST_TESTED_AT(0x0613))
       struct dummy
       {
         unordered_multimap<K, T, H, P, A> x;
       };
 #endif
       return m1.table_.equals_equiv(m2.table_);
     }
 
     template <class K, class T, class H, class P, class A>
     inline bool operator!=(unordered_multimap<K, T, H, P, A> const& m1,
       unordered_multimap<K, T, H, P, A> const& m2)
     {
 #if BOOST_WORKAROUND(BOOST_CODEGEARC, BOOST_TESTED_AT(0x0613))
       struct dummy
       {
         unordered_multimap<K, T, H, P, A> x;
       };
 #endif
       return !m1.table_.equals_equiv(m2.table_);
     }
 
     template <class K, class T, class H, class P, class A>
     inline void swap(unordered_multimap<K, T, H, P, A>& m1,
       unordered_multimap<K, T, H, P, A>& m2) noexcept(noexcept(m1.swap(m2)))
     {
 #if BOOST_WORKAROUND(BOOST_CODEGEARC, BOOST_TESTED_AT(0x0613))
       struct dummy
       {
         unordered_multimap<K, T, H, P, A> x;
       };
 #endif
       m1.swap(m2);
     }
 
     template <class K, class T, class H, class P, class A, class Predicate>
     typename unordered_multimap<K, T, H, P, A>::size_type erase_if(
       unordered_multimap<K, T, H, P, A>& c, Predicate pred)
     {
       return detail::erase_if(c, pred);
     }
 
     template <typename N, class K, class T, class A> class node_handle_map
     {
       template <typename Types> friend struct ::boost::unordered::detail::table;
       template <class K2, class T2, class H2, class P2, class A2>
       friend class boost::unordered::unordered_map;
       template <class K2, class T2, class H2, class P2, class A2>
       friend class boost::unordered::unordered_multimap;
 
       typedef typename boost::allocator_rebind<A, std::pair<K const, T> >::type
         value_allocator;
 
       typedef N node;
       typedef typename boost::allocator_rebind<A, node>::type node_allocator;
 
       typedef
         typename boost::allocator_pointer<node_allocator>::type node_pointer;
 
     public:
       typedef K key_type;
       typedef T mapped_type;
       typedef A allocator_type;
 
     private:
       node_pointer ptr_;
       boost::unordered::detail::optional<value_allocator> alloc_;
 
       node_handle_map(node_pointer ptr, allocator_type const& a)
           : ptr_(ptr), alloc_(a)
       {
       }
 
     public:
       constexpr node_handle_map() noexcept : ptr_(), alloc_() {}
       node_handle_map(node_handle_map const&) = delete;
       node_handle_map& operator=(node_handle_map const&) = delete;
 
       ~node_handle_map()
       {
         if (ptr_) {
           node_allocator node_alloc(*alloc_);
           boost::unordered::detail::node_tmp<node_allocator> tmp(
             ptr_, node_alloc);
         }
       }
 
       node_handle_map(node_handle_map&& n) noexcept
           : ptr_(n.ptr_),
             alloc_(std::move(n.alloc_))
       {
         n.ptr_ = node_pointer();
       }
 
       node_handle_map& operator=(node_handle_map&& n)
       {
         BOOST_ASSERT(!alloc_.has_value() ||
                      boost::allocator_propagate_on_container_move_assignment<
                        value_allocator>::type::value ||
                      (n.alloc_.has_value() && alloc_ == n.alloc_));
 
         if (ptr_) {
           node_allocator node_alloc(*alloc_);
           boost::unordered::detail::node_tmp<node_allocator> tmp(
             ptr_, node_alloc);
           ptr_ = node_pointer();
         }
 
         if (!alloc_.has_value() ||
             boost::allocator_propagate_on_container_move_assignment<
               value_allocator>::type::value) {
           alloc_ = std::move(n.alloc_);
         }
         ptr_ = n.ptr_;
         n.ptr_ = node_pointer();
 
         return *this;
       }
 
       key_type& key() const
       {
         return const_cast<key_type&>(ptr_->value().first);
       }
 
       mapped_type& mapped() const { return ptr_->value().second; }
 
       allocator_type get_allocator() const { return *alloc_; }
 
       explicit operator bool() const noexcept
       {
         return !this->operator!();
       }
 
       bool operator!() const noexcept { return ptr_ ? 0 : 1; }
 
       BOOST_ATTRIBUTE_NODISCARD bool empty() const noexcept
       {
         return ptr_ ? 0 : 1;
       }
 
       void swap(node_handle_map& n)
         noexcept(boost::allocator_propagate_on_container_swap<
                    value_allocator>::type::value ||
                  boost::allocator_is_always_equal<value_allocator>::type::value)
       {
 
         BOOST_ASSERT(!alloc_.has_value() || !n.alloc_.has_value() ||
                      boost::allocator_propagate_on_container_swap<
                        value_allocator>::type::value ||
                      alloc_ == n.alloc_);
         if (boost::allocator_propagate_on_container_swap<
               value_allocator>::type::value ||
             !alloc_.has_value() || !n.alloc_.has_value()) {
           boost::core::invoke_swap(alloc_, n.alloc_);
         }
         boost::core::invoke_swap(ptr_, n.ptr_);
       }
     };
 
     template <class N, class K, class T, class A>
     void swap(node_handle_map<N, K, T, A>& x, node_handle_map<N, K, T, A>& y)
       noexcept(noexcept(x.swap(y)))
     {
       x.swap(y);
     }
 
     template <class Iter, class NodeType> struct insert_return_type_map
     {
     public:
       Iter position;
       bool inserted;
       NodeType node;
 
       insert_return_type_map() : position(), inserted(false), node() {}
       insert_return_type_map(insert_return_type_map const&) = delete;
       insert_return_type_map& operator=(insert_return_type_map const&) = delete;
 
       insert_return_type_map(insert_return_type_map&& x) noexcept
           : position(x.position),
             inserted(x.inserted),
             node(std::move(x.node))
       {
       }
 
       insert_return_type_map& operator=(insert_return_type_map&& x)
       {
         inserted = x.inserted;
         position = x.position;
         node = std::move(x.node);
         return *this;
       }
     };
 
     template <class Iter, class NodeType>
     void swap(insert_return_type_map<Iter, NodeType>& x,
       insert_return_type_map<Iter, NodeType>& y)
     {
       boost::core::invoke_swap(x.node, y.node);
       boost::core::invoke_swap(x.inserted, y.inserted);
       boost::core::invoke_swap(x.position, y.position);
     }
   } // namespace unordered
 
   namespace serialization {
     template <class K, class T, class H, class P, class A>
     struct version<boost::unordered_map<K, T, H, P, A> >
     {
       BOOST_STATIC_CONSTANT(int, value = 1);
     };
 
     template <class K, class T, class H, class P, class A>
     struct version<boost::unordered_multimap<K, T, H, P, A> >
     {
       BOOST_STATIC_CONSTANT(int, value = 1);
     };
   } // namespace serialization
 
 } // namespace boost
 
 #if defined(BOOST_MSVC)
 #pragma warning(pop)
 #endif
 
 #endif // BOOST_UNORDERED_UNORDERED_MAP_HPP_INCLUDED