intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 1521 insertions, 0 deletions

diff --git a/contrib/libs/cxxsupp/libcxx/include/set b/contrib/libs/cxxsupp/libcxx/include/set
new file mode 100644
index 0000000000..46b515ba53
--- /dev/null
+++ b/contrib/libs/cxxsupp/libcxx/include/set
@@ -0,0 +1,1521 @@
+// -*- C++ -*-
+//===---------------------------- set -------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_SET
+#define _LIBCPP_SET
+
+/*
+
+    set synopsis
+
+namespace std
+{
+
+template <class Key, class Compare = less<Key>,
+          class Allocator = allocator<Key>>
+class set
+{
+public:
+    // types:
+    typedef Key                                      key_type;
+    typedef key_type                                 value_type;
+    typedef Compare                                  key_compare;
+    typedef key_compare                              value_compare;
+    typedef Allocator                                allocator_type;
+    typedef typename allocator_type::reference       reference;
+    typedef typename allocator_type::const_reference const_reference;
+    typedef typename allocator_type::size_type       size_type;
+    typedef typename allocator_type::difference_type difference_type;
+    typedef typename allocator_type::pointer         pointer;
+    typedef typename allocator_type::const_pointer   const_pointer;
+
+    typedef implementation-defined                   iterator;
+    typedef implementation-defined                   const_iterator;
+    typedef std::reverse_iterator<iterator>          reverse_iterator;
+    typedef std::reverse_iterator<const_iterator>    const_reverse_iterator;
+    typedef unspecified                              node_type;               // C++17
+    typedef INSERT_RETURN_TYPE<iterator, node_type>  insert_return_type;      // C++17
+
+    // construct/copy/destroy:
+    set()
+        noexcept(
+            is_nothrow_default_constructible<allocator_type>::value &&
+            is_nothrow_default_constructible<key_compare>::value &&
+            is_nothrow_copy_constructible<key_compare>::value);
+    explicit set(const value_compare& comp);
+    set(const value_compare& comp, const allocator_type& a);
+    template <class InputIterator>
+        set(InputIterator first, InputIterator last,
+            const value_compare& comp = value_compare());
+    template <class InputIterator>
+        set(InputIterator first, InputIterator last, const value_compare& comp,
+            const allocator_type& a);
+    set(const set& s);
+    set(set&& s)
+        noexcept(
+            is_nothrow_move_constructible<allocator_type>::value &&
+            is_nothrow_move_constructible<key_compare>::value);
+    explicit set(const allocator_type& a);
+    set(const set& s, const allocator_type& a);
+    set(set&& s, const allocator_type& a);
+    set(initializer_list<value_type> il, const value_compare& comp = value_compare());
+    set(initializer_list<value_type> il, const value_compare& comp,
+        const allocator_type& a);
+    template <class InputIterator>
+        set(InputIterator first, InputIterator last, const allocator_type& a)
+            : set(first, last, Compare(), a) {}  // C++14
+    set(initializer_list<value_type> il, const allocator_type& a)
+        : set(il, Compare(), a) {}  // C++14
+    ~set();
+
+    set& operator=(const set& s);
+    set& operator=(set&& s)
+        noexcept(
+            allocator_type::propagate_on_container_move_assignment::value &&
+            is_nothrow_move_assignable<allocator_type>::value &&
+            is_nothrow_move_assignable<key_compare>::value);
+    set& operator=(initializer_list<value_type> il);
+
+    // iterators:
+          iterator begin() noexcept;
+    const_iterator begin() const noexcept;
+          iterator end() noexcept;
+    const_iterator end()   const noexcept;
+
+          reverse_iterator rbegin() noexcept;
+    const_reverse_iterator rbegin() const noexcept;
+          reverse_iterator rend() noexcept;
+    const_reverse_iterator rend()   const noexcept;
+
+    const_iterator         cbegin()  const noexcept;
+    const_iterator         cend()    const noexcept;
+    const_reverse_iterator crbegin() const noexcept;
+    const_reverse_iterator crend()   const noexcept;
+
+    // capacity:
+    bool      empty()    const noexcept;
+    size_type size()     const noexcept;
+    size_type max_size() const noexcept;
+
+    // modifiers:
+    template <class... Args>
+        pair<iterator, bool> emplace(Args&&... args);
+    template <class... Args>
+        iterator emplace_hint(const_iterator position, Args&&... args);
+    pair<iterator,bool> insert(const value_type& v);
+    pair<iterator,bool> insert(value_type&& v);
+    iterator insert(const_iterator position, const value_type& v);
+    iterator insert(const_iterator position, value_type&& v);
+    template <class InputIterator>
+        void insert(InputIterator first, InputIterator last);
+    void insert(initializer_list<value_type> il);
+
+    node_type extract(const_iterator position);                                       // C++17
+    node_type extract(const key_type& x);                                             // C++17
+    insert_return_type insert(node_type&& nh);                                        // C++17
+    iterator insert(const_iterator hint, node_type&& nh);                             // C++17
+
+    iterator  erase(const_iterator position);
+    iterator  erase(iterator position);  // C++14
+    size_type erase(const key_type& k);
+    iterator  erase(const_iterator first, const_iterator last);
+    void clear() noexcept;
+
+    template<class C2>
+      void merge(set<Key, C2, Allocator>& source);         // C++17
+    template<class C2>
+      void merge(set<Key, C2, Allocator>&& source);        // C++17
+    template<class C2>
+      void merge(multiset<Key, C2, Allocator>& source);    // C++17
+    template<class C2>
+      void merge(multiset<Key, C2, Allocator>&& source);   // C++17
+
+    void swap(set& s)
+        noexcept(
+            __is_nothrow_swappable<key_compare>::value &&
+            (!allocator_type::propagate_on_container_swap::value ||
+             __is_nothrow_swappable<allocator_type>::value));
+
+    // observers:
+    allocator_type get_allocator() const noexcept;
+    key_compare    key_comp()      const;
+    value_compare  value_comp()    const;
+
+    // set operations:
+          iterator find(const key_type& k);
+    const_iterator find(const key_type& k) const;
+    template<typename K>
+        iterator find(const K& x);
+    template<typename K>
+        const_iterator find(const K& x) const;  // C++14
+
+    template<typename K>
+        size_type count(const K& x) const;        // C++14
+    size_type      count(const key_type& k) const;
+
+        bool contains(const key_type& x) const; // C++20
+    template<class K> bool contains(const K& x) const; // C++20
+
+          iterator lower_bound(const key_type& k);
+    const_iterator lower_bound(const key_type& k) const;
+    template<typename K>
+        iterator lower_bound(const K& x);              // C++14
+    template<typename K>
+        const_iterator lower_bound(const K& x) const;  // C++14
+
+          iterator upper_bound(const key_type& k);
+    const_iterator upper_bound(const key_type& k) const;
+    template<typename K>
+        iterator upper_bound(const K& x);              // C++14
+    template<typename K>
+        const_iterator upper_bound(const K& x) const;  // C++14
+    pair<iterator,iterator>             equal_range(const key_type& k);
+    pair<const_iterator,const_iterator> equal_range(const key_type& k) const;
+    template<typename K>
+        pair<iterator,iterator>             equal_range(const K& x);        // C++14
+    template<typename K>
+        pair<const_iterator,const_iterator> equal_range(const K& x) const;  // C++14
+};
+
+template <class Key, class Compare, class Allocator>
+bool
+operator==(const set<Key, Compare, Allocator>& x,
+           const set<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator< (const set<Key, Compare, Allocator>& x,
+           const set<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator!=(const set<Key, Compare, Allocator>& x,
+           const set<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator> (const set<Key, Compare, Allocator>& x,
+           const set<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator>=(const set<Key, Compare, Allocator>& x,
+           const set<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator<=(const set<Key, Compare, Allocator>& x,
+           const set<Key, Compare, Allocator>& y);
+
+// specialized algorithms:
+template <class Key, class Compare, class Allocator>
+void
+swap(set<Key, Compare, Allocator>& x, set<Key, Compare, Allocator>& y)
+    noexcept(noexcept(x.swap(y)));
+
+template <class Key, class Compare, class Allocator, class Predicate>
+typename set<Key, Compare, Allocator>::size_type
+erase_if(set<Key, Compare, Allocator>& c, Predicate pred);  // C++20
+
+template <class Key, class Compare = less<Key>,
+          class Allocator = allocator<Key>>
+class multiset
+{
+public:
+    // types:
+    typedef Key                                      key_type;
+    typedef key_type                                 value_type;
+    typedef Compare                                  key_compare;
+    typedef key_compare                              value_compare;
+    typedef Allocator                                allocator_type;
+    typedef typename allocator_type::reference       reference;
+    typedef typename allocator_type::const_reference const_reference;
+    typedef typename allocator_type::size_type       size_type;
+    typedef typename allocator_type::difference_type difference_type;
+    typedef typename allocator_type::pointer         pointer;
+    typedef typename allocator_type::const_pointer   const_pointer;
+
+    typedef implementation-defined                   iterator;
+    typedef implementation-defined                   const_iterator;
+    typedef std::reverse_iterator<iterator>          reverse_iterator;
+    typedef std::reverse_iterator<const_iterator>    const_reverse_iterator;
+    typedef unspecified                              node_type;               // C++17
+
+    // construct/copy/destroy:
+    multiset()
+        noexcept(
+            is_nothrow_default_constructible<allocator_type>::value &&
+            is_nothrow_default_constructible<key_compare>::value &&
+            is_nothrow_copy_constructible<key_compare>::value);
+    explicit multiset(const value_compare& comp);
+    multiset(const value_compare& comp, const allocator_type& a);
+    template <class InputIterator>
+        multiset(InputIterator first, InputIterator last,
+                 const value_compare& comp = value_compare());
+    template <class InputIterator>
+        multiset(InputIterator first, InputIterator last,
+                 const value_compare& comp, const allocator_type& a);
+    multiset(const multiset& s);
+    multiset(multiset&& s)
+        noexcept(
+            is_nothrow_move_constructible<allocator_type>::value &&
+            is_nothrow_move_constructible<key_compare>::value);
+    explicit multiset(const allocator_type& a);
+    multiset(const multiset& s, const allocator_type& a);
+    multiset(multiset&& s, const allocator_type& a);
+    multiset(initializer_list<value_type> il, const value_compare& comp = value_compare());
+    multiset(initializer_list<value_type> il, const value_compare& comp,
+             const allocator_type& a);
+    template <class InputIterator>
+        multiset(InputIterator first, InputIterator last, const allocator_type& a)
+            : set(first, last, Compare(), a) {}  // C++14
+    multiset(initializer_list<value_type> il, const allocator_type& a)
+        : set(il, Compare(), a) {}  // C++14
+    ~multiset();
+
+    multiset& operator=(const multiset& s);
+    multiset& operator=(multiset&& s)
+        noexcept(
+            allocator_type::propagate_on_container_move_assignment::value &&
+            is_nothrow_move_assignable<allocator_type>::value &&
+            is_nothrow_move_assignable<key_compare>::value);
+    multiset& operator=(initializer_list<value_type> il);
+
+    // iterators:
+          iterator begin() noexcept;
+    const_iterator begin() const noexcept;
+          iterator end() noexcept;
+    const_iterator end()   const noexcept;
+
+          reverse_iterator rbegin() noexcept;
+    const_reverse_iterator rbegin() const noexcept;
+          reverse_iterator rend() noexcept;
+    const_reverse_iterator rend()   const noexcept;
+
+    const_iterator         cbegin()  const noexcept;
+    const_iterator         cend()    const noexcept;
+    const_reverse_iterator crbegin() const noexcept;
+    const_reverse_iterator crend()   const noexcept;
+
+    // capacity:
+    bool      empty()    const noexcept;
+    size_type size()     const noexcept;
+    size_type max_size() const noexcept;
+
+    // modifiers:
+    template <class... Args>
+        iterator emplace(Args&&... args);
+    template <class... Args>
+        iterator emplace_hint(const_iterator position, Args&&... args);
+    iterator insert(const value_type& v);
+    iterator insert(value_type&& v);
+    iterator insert(const_iterator position, const value_type& v);
+    iterator insert(const_iterator position, value_type&& v);
+    template <class InputIterator>
+        void insert(InputIterator first, InputIterator last);
+    void insert(initializer_list<value_type> il);
+
+    node_type extract(const_iterator position);                                       // C++17
+    node_type extract(const key_type& x);                                             // C++17
+    iterator insert(node_type&& nh);                                                  // C++17
+    iterator insert(const_iterator hint, node_type&& nh);                             // C++17
+
+    iterator  erase(const_iterator position);
+    iterator  erase(iterator position);  // C++14
+    size_type erase(const key_type& k);
+    iterator  erase(const_iterator first, const_iterator last);
+    void clear() noexcept;
+
+    template<class C2>
+      void merge(multiset<Key, C2, Allocator>& source);    // C++17
+    template<class C2>
+      void merge(multiset<Key, C2, Allocator>&& source);   // C++17
+    template<class C2>
+      void merge(set<Key, C2, Allocator>& source);         // C++17
+    template<class C2>
+      void merge(set<Key, C2, Allocator>&& source);        // C++17
+
+    void swap(multiset& s)
+        noexcept(
+            __is_nothrow_swappable<key_compare>::value &&
+            (!allocator_type::propagate_on_container_swap::value ||
+             __is_nothrow_swappable<allocator_type>::value));
+
+    // observers:
+    allocator_type get_allocator() const noexcept;
+    key_compare    key_comp()      const;
+    value_compare  value_comp()    const;
+
+    // set operations:
+          iterator find(const key_type& k);
+    const_iterator find(const key_type& k) const;
+    template<typename K>
+        iterator find(const K& x);
+    template<typename K>
+        const_iterator find(const K& x) const;  // C++14
+
+    template<typename K>
+        size_type count(const K& x) const;      // C++14
+    size_type      count(const key_type& k) const;
+
+        bool contains(const key_type& x) const; // C++20
+    template<class K> bool contains(const K& x) const; // C++20
+
+          iterator lower_bound(const key_type& k);
+    const_iterator lower_bound(const key_type& k) const;
+    template<typename K>
+        iterator lower_bound(const K& x);              // C++14
+    template<typename K>
+        const_iterator lower_bound(const K& x) const;  // C++14
+
+          iterator upper_bound(const key_type& k);
+    const_iterator upper_bound(const key_type& k) const;
+    template<typename K>
+        iterator upper_bound(const K& x);              // C++14
+    template<typename K>
+        const_iterator upper_bound(const K& x) const;  // C++14
+
+    pair<iterator,iterator>             equal_range(const key_type& k);
+    pair<const_iterator,const_iterator> equal_range(const key_type& k) const;
+    template<typename K>
+        pair<iterator,iterator>             equal_range(const K& x);        // C++14
+    template<typename K>
+        pair<const_iterator,const_iterator> equal_range(const K& x) const;  // C++14
+};
+
+template <class Key, class Compare, class Allocator>
+bool
+operator==(const multiset<Key, Compare, Allocator>& x,
+           const multiset<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator< (const multiset<Key, Compare, Allocator>& x,
+           const multiset<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator!=(const multiset<Key, Compare, Allocator>& x,
+           const multiset<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator> (const multiset<Key, Compare, Allocator>& x,
+           const multiset<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator>=(const multiset<Key, Compare, Allocator>& x,
+           const multiset<Key, Compare, Allocator>& y);
+
+template <class Key, class Compare, class Allocator>
+bool
+operator<=(const multiset<Key, Compare, Allocator>& x,
+           const multiset<Key, Compare, Allocator>& y);
+
+// specialized algorithms:
+template <class Key, class Compare, class Allocator>
+void
+swap(multiset<Key, Compare, Allocator>& x, multiset<Key, Compare, Allocator>& y)
+    noexcept(noexcept(x.swap(y)));
+
+template <class Key, class Compare, class Allocator, class Predicate>
+typename multiset<Key, Compare, Allocator>::size_type
+erase_if(multiset<Key, Compare, Allocator>& c, Predicate pred);  // C++20
+
+}  // std
+
+*/
+
+#include <__config>
+#include <__debug>
+#include <__functional/is_transparent.h>
+#include <__node_handle>
+#include <__tree>
+#include <__utility/forward.h>
+#include <compare>
+#include <functional>
+#include <initializer_list>
+#include <iterator> // __libcpp_erase_if_container
+#include <version>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Key, class _Compare, class _Allocator>
+class multiset;
+
+template <class _Key, class _Compare = less<_Key>,
+          class _Allocator = allocator<_Key> >
+class _LIBCPP_TEMPLATE_VIS set
+{
+public:
+    // types:
+    typedef _Key                                     key_type;
+    typedef key_type                                 value_type;
+    typedef _Compare                                 key_compare;
+    typedef key_compare                              value_compare;
+    typedef __identity_t<_Allocator>                 allocator_type;
+    typedef value_type&                              reference;
+    typedef const value_type&                        const_reference;
+
+    static_assert((is_same<typename allocator_type::value_type, value_type>::value),
+                  "Allocator::value_type must be same type as value_type");
+
+private:
+    typedef __tree<value_type, value_compare, allocator_type> __base;
+    typedef allocator_traits<allocator_type>                  __alloc_traits;
+    typedef typename __base::__node_holder                    __node_holder;
+
+    __base __tree_;
+
+public:
+    typedef typename __base::pointer               pointer;
+    typedef typename __base::const_pointer         const_pointer;
+    typedef typename __base::size_type             size_type;
+    typedef typename __base::difference_type       difference_type;
+    typedef typename __base::const_iterator        iterator;
+    typedef typename __base::const_iterator        const_iterator;
+    typedef _VSTD::reverse_iterator<iterator>       reverse_iterator;
+    typedef _VSTD::reverse_iterator<const_iterator> const_reverse_iterator;
+
+#if _LIBCPP_STD_VER > 14
+    typedef __set_node_handle<typename __base::__node, allocator_type> node_type;
+    typedef __insert_return_type<iterator, node_type> insert_return_type;
+#endif
+
+    template <class _Key2, class _Compare2, class _Alloc2>
+        friend class _LIBCPP_TEMPLATE_VIS set;
+    template <class _Key2, class _Compare2, class _Alloc2>
+        friend class _LIBCPP_TEMPLATE_VIS multiset;
+
+    _LIBCPP_INLINE_VISIBILITY
+    set()
+        _NOEXCEPT_(
+            is_nothrow_default_constructible<allocator_type>::value &&
+            is_nothrow_default_constructible<key_compare>::value &&
+            is_nothrow_copy_constructible<key_compare>::value)
+        : __tree_(value_compare()) {}
+
+    _LIBCPP_INLINE_VISIBILITY
+    explicit set(const value_compare& __comp)
+        _NOEXCEPT_(
+            is_nothrow_default_constructible<allocator_type>::value &&
+            is_nothrow_copy_constructible<key_compare>::value)
+        : __tree_(__comp) {}
+
+    _LIBCPP_INLINE_VISIBILITY
+    explicit set(const value_compare& __comp, const allocator_type& __a)
+        : __tree_(__comp, __a) {}
+    template <class _InputIterator>
+        _LIBCPP_INLINE_VISIBILITY
+        set(_InputIterator __f, _InputIterator __l,
+            const value_compare& __comp = value_compare())
+        : __tree_(__comp)
+        {
+            insert(__f, __l);
+        }
+
+    template <class _InputIterator>
+        _LIBCPP_INLINE_VISIBILITY
+        set(_InputIterator __f, _InputIterator __l, const value_compare& __comp,
+            const allocator_type& __a)
+        : __tree_(__comp, __a)
+        {
+            insert(__f, __l);
+        }
+
+#if _LIBCPP_STD_VER > 11
+        template <class _InputIterator>
+        _LIBCPP_INLINE_VISIBILITY
+        set(_InputIterator __f, _InputIterator __l, const allocator_type& __a)
+            : set(__f, __l, key_compare(), __a) {}
+#endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    set(const set& __s)
+        : __tree_(__s.__tree_)
+        {
+            insert(__s.begin(), __s.end());
+        }
+
+    _LIBCPP_INLINE_VISIBILITY
+    set& operator=(const set& __s)
+        {
+            __tree_ = __s.__tree_;
+            return *this;
+        }
+
+#ifndef _LIBCPP_CXX03_LANG
+    _LIBCPP_INLINE_VISIBILITY
+    set(set&& __s)
+        _NOEXCEPT_(is_nothrow_move_constructible<__base>::value)
+        : __tree_(_VSTD::move(__s.__tree_)) {}
+#endif // _LIBCPP_CXX03_LANG
+
+    _LIBCPP_INLINE_VISIBILITY
+    explicit set(const allocator_type& __a)
+        : __tree_(__a) {}
+
+    _LIBCPP_INLINE_VISIBILITY
+    set(const set& __s, const allocator_type& __a)
+        : __tree_(__s.__tree_.value_comp(), __a)
+        {
+            insert(__s.begin(), __s.end());
+        }
+
+#ifndef _LIBCPP_CXX03_LANG
+    set(set&& __s, const allocator_type& __a);
+
+    _LIBCPP_INLINE_VISIBILITY
+    set(initializer_list<value_type> __il, const value_compare& __comp = value_compare())
+        : __tree_(__comp)
+        {
+            insert(__il.begin(), __il.end());
+        }
+
+    _LIBCPP_INLINE_VISIBILITY
+    set(initializer_list<value_type> __il, const value_compare& __comp,
+        const allocator_type& __a)
+        : __tree_(__comp, __a)
+        {
+            insert(__il.begin(), __il.end());
+        }
+
+#if _LIBCPP_STD_VER > 11
+    _LIBCPP_INLINE_VISIBILITY
+    set(initializer_list<value_type> __il, const allocator_type& __a)
+        : set(__il, key_compare(), __a) {}
+#endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    set& operator=(initializer_list<value_type> __il)
+        {
+            __tree_.__assign_unique(__il.begin(), __il.end());
+            return *this;
+        }
+
+    _LIBCPP_INLINE_VISIBILITY
+    set& operator=(set&& __s)
+        _NOEXCEPT_(is_nothrow_move_assignable<__base>::value)
+        {
+            __tree_ = _VSTD::move(__s.__tree_);
+            return *this;
+        }
+#endif // _LIBCPP_CXX03_LANG
+
+    _LIBCPP_INLINE_VISIBILITY
+    ~set() {
+        static_assert(sizeof(__diagnose_non_const_comparator<_Key, _Compare>()), "");
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+          iterator begin() _NOEXCEPT       {return __tree_.begin();}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator begin() const _NOEXCEPT {return __tree_.begin();}
+    _LIBCPP_INLINE_VISIBILITY
+          iterator end() _NOEXCEPT         {return __tree_.end();}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator end()   const _NOEXCEPT {return __tree_.end();}
+
+    _LIBCPP_INLINE_VISIBILITY
+          reverse_iterator rbegin() _NOEXCEPT
+            {return reverse_iterator(end());}
+    _LIBCPP_INLINE_VISIBILITY
+    const_reverse_iterator rbegin() const _NOEXCEPT
+        {return const_reverse_iterator(end());}
+    _LIBCPP_INLINE_VISIBILITY
+          reverse_iterator rend() _NOEXCEPT
+            {return reverse_iterator(begin());}
+    _LIBCPP_INLINE_VISIBILITY
+    const_reverse_iterator rend() const _NOEXCEPT
+        {return const_reverse_iterator(begin());}
+
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator cbegin()  const _NOEXCEPT {return begin();}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator cend() const _NOEXCEPT {return end();}
+    _LIBCPP_INLINE_VISIBILITY
+    const_reverse_iterator crbegin() const _NOEXCEPT {return rbegin();}
+    _LIBCPP_INLINE_VISIBILITY
+    const_reverse_iterator crend() const _NOEXCEPT {return rend();}
+
+    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
+    bool empty() const _NOEXCEPT {return __tree_.size() == 0;}
+    _LIBCPP_INLINE_VISIBILITY
+    size_type size() const _NOEXCEPT {return __tree_.size();}
+    _LIBCPP_INLINE_VISIBILITY
+    size_type max_size() const _NOEXCEPT {return __tree_.max_size();}
+
+    // modifiers:
+#ifndef _LIBCPP_CXX03_LANG
+    template <class... _Args>
+        _LIBCPP_INLINE_VISIBILITY
+        pair<iterator, bool> emplace(_Args&&... __args)
+            {return __tree_.__emplace_unique(_VSTD::forward<_Args>(__args)...);}
+    template <class... _Args>
+        _LIBCPP_INLINE_VISIBILITY
+        iterator emplace_hint(const_iterator __p, _Args&&... __args)
+            {return __tree_.__emplace_hint_unique(__p, _VSTD::forward<_Args>(__args)...);}
+#endif // _LIBCPP_CXX03_LANG
+
+    _LIBCPP_INLINE_VISIBILITY
+    pair<iterator,bool> insert(const value_type& __v)
+        {return __tree_.__insert_unique(__v);}
+    _LIBCPP_INLINE_VISIBILITY
+    iterator insert(const_iterator __p, const value_type& __v)
+        {return __tree_.__insert_unique(__p, __v);}
+
+    template <class _InputIterator>
+        _LIBCPP_INLINE_VISIBILITY
+        void insert(_InputIterator __f, _InputIterator __l)
+        {
+            for (const_iterator __e = cend(); __f != __l; ++__f)
+                __tree_.__insert_unique(__e, *__f);
+        }
+
+#ifndef _LIBCPP_CXX03_LANG
+    _LIBCPP_INLINE_VISIBILITY
+    pair<iterator,bool> insert(value_type&& __v)
+        {return __tree_.__insert_unique(_VSTD::move(__v));}
+
+    _LIBCPP_INLINE_VISIBILITY
+    iterator insert(const_iterator __p, value_type&& __v)
+        {return __tree_.__insert_unique(__p, _VSTD::move(__v));}
+
+    _LIBCPP_INLINE_VISIBILITY
+    void insert(initializer_list<value_type> __il)
+        {insert(__il.begin(), __il.end());}
+#endif // _LIBCPP_CXX03_LANG
+
+    _LIBCPP_INLINE_VISIBILITY
+    iterator  erase(const_iterator __p) {return __tree_.erase(__p);}
+    _LIBCPP_INLINE_VISIBILITY
+    size_type erase(const key_type& __k)
+        {return __tree_.__erase_unique(__k);}
+    _LIBCPP_INLINE_VISIBILITY
+    iterator  erase(const_iterator __f, const_iterator __l)
+        {return __tree_.erase(__f, __l);}
+    _LIBCPP_INLINE_VISIBILITY
+    void clear() _NOEXCEPT {__tree_.clear();}
+
+#if _LIBCPP_STD_VER > 14
+    _LIBCPP_INLINE_VISIBILITY
+    insert_return_type insert(node_type&& __nh)
+    {
+        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
+            "node_type with incompatible allocator passed to set::insert()");
+        return __tree_.template __node_handle_insert_unique<
+            node_type, insert_return_type>(_VSTD::move(__nh));
+    }
+    _LIBCPP_INLINE_VISIBILITY
+    iterator insert(const_iterator __hint, node_type&& __nh)
+    {
+        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
+            "node_type with incompatible allocator passed to set::insert()");
+        return __tree_.template __node_handle_insert_unique<node_type>(
+            __hint, _VSTD::move(__nh));
+    }
+    _LIBCPP_INLINE_VISIBILITY
+    node_type extract(key_type const& __key)
+    {
+        return __tree_.template __node_handle_extract<node_type>(__key);
+    }
+    _LIBCPP_INLINE_VISIBILITY
+    node_type extract(const_iterator __it)
+    {
+        return __tree_.template __node_handle_extract<node_type>(__it);
+    }
+    template <class _Compare2>
+    _LIBCPP_INLINE_VISIBILITY
+    void merge(set<key_type, _Compare2, allocator_type>& __source)
+    {
+        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
+                       "merging container with incompatible allocator");
+        __tree_.__node_handle_merge_unique(__source.__tree_);
+    }
+    template <class _Compare2>
+    _LIBCPP_INLINE_VISIBILITY
+    void merge(set<key_type, _Compare2, allocator_type>&& __source)
+    {
+        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
+                       "merging container with incompatible allocator");
+        __tree_.__node_handle_merge_unique(__source.__tree_);
+    }
+    template <class _Compare2>
+    _LIBCPP_INLINE_VISIBILITY
+    void merge(multiset<key_type, _Compare2, allocator_type>& __source)
+    {
+        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
+                       "merging container with incompatible allocator");
+        __tree_.__node_handle_merge_unique(__source.__tree_);
+    }
+    template <class _Compare2>
+    _LIBCPP_INLINE_VISIBILITY
+    void merge(multiset<key_type, _Compare2, allocator_type>&& __source)
+    {
+        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
+                       "merging container with incompatible allocator");
+        __tree_.__node_handle_merge_unique(__source.__tree_);
+    }
+#endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    void swap(set& __s) _NOEXCEPT_(__is_nothrow_swappable<__base>::value)
+        {__tree_.swap(__s.__tree_);}
+
+    _LIBCPP_INLINE_VISIBILITY
+    allocator_type get_allocator() const _NOEXCEPT {return __tree_.__alloc();}
+    _LIBCPP_INLINE_VISIBILITY
+    key_compare    key_comp()      const {return __tree_.value_comp();}
+    _LIBCPP_INLINE_VISIBILITY
+    value_compare  value_comp()    const {return __tree_.value_comp();}
+
+    // set operations:
+    _LIBCPP_INLINE_VISIBILITY
+    iterator find(const key_type& __k)             {return __tree_.find(__k);}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator find(const key_type& __k) const {return __tree_.find(__k);}
+#if _LIBCPP_STD_VER > 11
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,iterator>::type
+    find(const _K2& __k)                           {return __tree_.find(__k);}
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,const_iterator>::type
+    find(const _K2& __k) const                     {return __tree_.find(__k);}
+#endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    size_type      count(const key_type& __k) const
+        {return __tree_.__count_unique(__k);}
+#if _LIBCPP_STD_VER > 11
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,size_type>::type
+    count(const _K2& __k) const                    {return __tree_.__count_multi(__k);}
+#endif
+
+#if _LIBCPP_STD_VER > 17
+    _LIBCPP_INLINE_VISIBILITY
+    bool contains(const key_type& __k) const {return find(__k) != end();}
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value, bool>::type
+    contains(const _K2& __k) const { return find(__k) != end(); }
+#endif // _LIBCPP_STD_VER > 17
+
+    _LIBCPP_INLINE_VISIBILITY
+    iterator lower_bound(const key_type& __k)
+        {return __tree_.lower_bound(__k);}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator lower_bound(const key_type& __k) const
+        {return __tree_.lower_bound(__k);}
+#if _LIBCPP_STD_VER > 11
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,iterator>::type
+    lower_bound(const _K2& __k)       {return __tree_.lower_bound(__k);}
+
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,const_iterator>::type
+    lower_bound(const _K2& __k) const {return __tree_.lower_bound(__k);}
+#endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    iterator upper_bound(const key_type& __k)
+        {return __tree_.upper_bound(__k);}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator upper_bound(const key_type& __k) const
+        {return __tree_.upper_bound(__k);}
+#if _LIBCPP_STD_VER > 11
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,iterator>::type
+    upper_bound(const _K2& __k)       {return __tree_.upper_bound(__k);}
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,const_iterator>::type
+    upper_bound(const _K2& __k) const {return __tree_.upper_bound(__k);}
+#endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    pair<iterator,iterator> equal_range(const key_type& __k)
+        {return __tree_.__equal_range_unique(__k);}
+    _LIBCPP_INLINE_VISIBILITY
+    pair<const_iterator,const_iterator> equal_range(const key_type& __k) const
+        {return __tree_.__equal_range_unique(__k);}
+#if _LIBCPP_STD_VER > 11
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,pair<iterator,iterator>>::type
+    equal_range(const _K2& __k)       {return __tree_.__equal_range_multi(__k);}
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,pair<const_iterator,const_iterator>>::type
+    equal_range(const _K2& __k) const {return __tree_.__equal_range_multi(__k);}
+#endif
+};
+
+#if _LIBCPP_STD_VER >= 17
+template<class _InputIterator,
+         class _Compare = less<__iter_value_type<_InputIterator>>,
+         class _Allocator = allocator<__iter_value_type<_InputIterator>>,
+         class = enable_if_t<__is_allocator<_Allocator>::value, void>,
+         class = enable_if_t<!__is_allocator<_Compare>::value, void>>
+set(_InputIterator, _InputIterator, _Compare = _Compare(), _Allocator = _Allocator())
+  -> set<__iter_value_type<_InputIterator>, _Compare, _Allocator>;
+
+template<class _Key, class _Compare = less<_Key>,
+         class _Allocator = allocator<_Key>,
+         class = enable_if_t<__is_allocator<_Allocator>::value, void>,
+         class = enable_if_t<!__is_allocator<_Compare>::value, void>>
+set(initializer_list<_Key>, _Compare = _Compare(), _Allocator = _Allocator())
+  -> set<_Key, _Compare, _Allocator>;
+
+template<class _InputIterator, class _Allocator,
+         class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+set(_InputIterator, _InputIterator, _Allocator)
+  -> set<__iter_value_type<_InputIterator>,
+         less<__iter_value_type<_InputIterator>>, _Allocator>;
+
+template<class _Key, class _Allocator,
+         class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+set(initializer_list<_Key>, _Allocator)
+  -> set<_Key, less<_Key>, _Allocator>;
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Compare, class _Allocator>
+set<_Key, _Compare, _Allocator>::set(set&& __s, const allocator_type& __a)
+    : __tree_(_VSTD::move(__s.__tree_), __a)
+{
+    if (__a != __s.get_allocator())
+    {
+        const_iterator __e = cend();
+        while (!__s.empty())
+            insert(__e, _VSTD::move(__s.__tree_.remove(__s.begin())->__value_));
+    }
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator==(const set<_Key, _Compare, _Allocator>& __x,
+           const set<_Key, _Compare, _Allocator>& __y)
+{
+    return __x.size() == __y.size() && _VSTD::equal(__x.begin(), __x.end(), __y.begin());
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator< (const set<_Key, _Compare, _Allocator>& __x,
+           const set<_Key, _Compare, _Allocator>& __y)
+{
+    return _VSTD::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator!=(const set<_Key, _Compare, _Allocator>& __x,
+           const set<_Key, _Compare, _Allocator>& __y)
+{
+    return !(__x == __y);
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator> (const set<_Key, _Compare, _Allocator>& __x,
+           const set<_Key, _Compare, _Allocator>& __y)
+{
+    return __y < __x;
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator>=(const set<_Key, _Compare, _Allocator>& __x,
+           const set<_Key, _Compare, _Allocator>& __y)
+{
+    return !(__x < __y);
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator<=(const set<_Key, _Compare, _Allocator>& __x,
+           const set<_Key, _Compare, _Allocator>& __y)
+{
+    return !(__y < __x);
+}
+
+// specialized algorithms:
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+void
+swap(set<_Key, _Compare, _Allocator>& __x,
+     set<_Key, _Compare, _Allocator>& __y)
+    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
+{
+    __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER > 17
+template <class _Key, class _Compare, class _Allocator, class _Predicate>
+inline _LIBCPP_INLINE_VISIBILITY
+    typename set<_Key, _Compare, _Allocator>::size_type
+    erase_if(set<_Key, _Compare, _Allocator>& __c, _Predicate __pred) {
+  return _VSTD::__libcpp_erase_if_container(__c, __pred);
+}
+#endif
+
+template <class _Key, class _Compare = less<_Key>,
+          class _Allocator = allocator<_Key> >
+class _LIBCPP_TEMPLATE_VIS multiset
+{
+public:
+    // types:
+    typedef _Key                                      key_type;
+    typedef key_type                                 value_type;
+    typedef _Compare                                  key_compare;
+    typedef key_compare                              value_compare;
+    typedef __identity_t<_Allocator>                 allocator_type;
+    typedef value_type&                              reference;
+    typedef const value_type&                        const_reference;
+
+    static_assert((is_same<typename allocator_type::value_type, value_type>::value),
+                  "Allocator::value_type must be same type as value_type");
+
+private:
+    typedef __tree<value_type, value_compare, allocator_type> __base;
+    typedef allocator_traits<allocator_type>                  __alloc_traits;
+    typedef typename __base::__node_holder                    __node_holder;
+
+    __base __tree_;
+
+public:
+    typedef typename __base::pointer               pointer;
+    typedef typename __base::const_pointer         const_pointer;
+    typedef typename __base::size_type             size_type;
+    typedef typename __base::difference_type       difference_type;
+    typedef typename __base::const_iterator        iterator;
+    typedef typename __base::const_iterator        const_iterator;
+    typedef _VSTD::reverse_iterator<iterator>       reverse_iterator;
+    typedef _VSTD::reverse_iterator<const_iterator> const_reverse_iterator;
+
+#if _LIBCPP_STD_VER > 14
+    typedef __set_node_handle<typename __base::__node, allocator_type> node_type;
+#endif
+
+    template <class _Key2, class _Compare2, class _Alloc2>
+        friend class _LIBCPP_TEMPLATE_VIS set;
+    template <class _Key2, class _Compare2, class _Alloc2>
+        friend class _LIBCPP_TEMPLATE_VIS multiset;
+
+    // construct/copy/destroy:
+    _LIBCPP_INLINE_VISIBILITY
+    multiset()
+        _NOEXCEPT_(
+            is_nothrow_default_constructible<allocator_type>::value &&
+            is_nothrow_default_constructible<key_compare>::value &&
+            is_nothrow_copy_constructible<key_compare>::value)
+        : __tree_(value_compare()) {}
+
+    _LIBCPP_INLINE_VISIBILITY
+    explicit multiset(const value_compare& __comp)
+        _NOEXCEPT_(
+            is_nothrow_default_constructible<allocator_type>::value &&
+            is_nothrow_copy_constructible<key_compare>::value)
+        : __tree_(__comp) {}
+
+    _LIBCPP_INLINE_VISIBILITY
+    explicit multiset(const value_compare& __comp, const allocator_type& __a)
+        : __tree_(__comp, __a) {}
+    template <class _InputIterator>
+        _LIBCPP_INLINE_VISIBILITY
+        multiset(_InputIterator __f, _InputIterator __l,
+                 const value_compare& __comp = value_compare())
+        : __tree_(__comp)
+        {
+            insert(__f, __l);
+        }
+
+#if _LIBCPP_STD_VER > 11
+        template <class _InputIterator>
+        _LIBCPP_INLINE_VISIBILITY
+        multiset(_InputIterator __f, _InputIterator __l, const allocator_type& __a)
+            : multiset(__f, __l, key_compare(), __a) {}
+#endif
+
+    template <class _InputIterator>
+        _LIBCPP_INLINE_VISIBILITY
+        multiset(_InputIterator __f, _InputIterator __l,
+                 const value_compare& __comp, const allocator_type& __a)
+        : __tree_(__comp, __a)
+        {
+            insert(__f, __l);
+        }
+
+    _LIBCPP_INLINE_VISIBILITY
+    multiset(const multiset& __s)
+        : __tree_(__s.__tree_.value_comp(),
+          __alloc_traits::select_on_container_copy_construction(__s.__tree_.__alloc()))
+        {
+            insert(__s.begin(), __s.end());
+        }
+
+    _LIBCPP_INLINE_VISIBILITY
+    multiset& operator=(const multiset& __s)
+        {
+            __tree_ = __s.__tree_;
+            return *this;
+        }
+
+#ifndef _LIBCPP_CXX03_LANG
+    _LIBCPP_INLINE_VISIBILITY
+    multiset(multiset&& __s)
+        _NOEXCEPT_(is_nothrow_move_constructible<__base>::value)
+        : __tree_(_VSTD::move(__s.__tree_)) {}
+
+    multiset(multiset&& __s, const allocator_type& __a);
+#endif // _LIBCPP_CXX03_LANG
+    _LIBCPP_INLINE_VISIBILITY
+    explicit multiset(const allocator_type& __a)
+        : __tree_(__a) {}
+    _LIBCPP_INLINE_VISIBILITY
+    multiset(const multiset& __s, const allocator_type& __a)
+        : __tree_(__s.__tree_.value_comp(), __a)
+        {
+            insert(__s.begin(), __s.end());
+        }
+
+#ifndef _LIBCPP_CXX03_LANG
+    _LIBCPP_INLINE_VISIBILITY
+    multiset(initializer_list<value_type> __il, const value_compare& __comp = value_compare())
+        : __tree_(__comp)
+        {
+            insert(__il.begin(), __il.end());
+        }
+
+    _LIBCPP_INLINE_VISIBILITY
+    multiset(initializer_list<value_type> __il, const value_compare& __comp,
+        const allocator_type& __a)
+        : __tree_(__comp, __a)
+        {
+            insert(__il.begin(), __il.end());
+        }
+
+#if _LIBCPP_STD_VER > 11
+    _LIBCPP_INLINE_VISIBILITY
+    multiset(initializer_list<value_type> __il, const allocator_type& __a)
+        : multiset(__il, key_compare(), __a) {}
+#endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    multiset& operator=(initializer_list<value_type> __il)
+        {
+            __tree_.__assign_multi(__il.begin(), __il.end());
+            return *this;
+        }
+
+    _LIBCPP_INLINE_VISIBILITY
+    multiset& operator=(multiset&& __s)
+        _NOEXCEPT_(is_nothrow_move_assignable<__base>::value)
+        {
+            __tree_ = _VSTD::move(__s.__tree_);
+            return *this;
+        }
+#endif // _LIBCPP_CXX03_LANG
+
+    _LIBCPP_INLINE_VISIBILITY
+    ~multiset() {
+        static_assert(sizeof(__diagnose_non_const_comparator<_Key, _Compare>()), "");
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+          iterator begin() _NOEXCEPT       {return __tree_.begin();}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator begin() const _NOEXCEPT {return __tree_.begin();}
+    _LIBCPP_INLINE_VISIBILITY
+          iterator end() _NOEXCEPT         {return __tree_.end();}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator end()   const _NOEXCEPT {return __tree_.end();}
+
+    _LIBCPP_INLINE_VISIBILITY
+          reverse_iterator rbegin() _NOEXCEPT
+            {return reverse_iterator(end());}
+    _LIBCPP_INLINE_VISIBILITY
+    const_reverse_iterator rbegin() const _NOEXCEPT
+        {return const_reverse_iterator(end());}
+    _LIBCPP_INLINE_VISIBILITY
+          reverse_iterator rend() _NOEXCEPT
+            {return       reverse_iterator(begin());}
+    _LIBCPP_INLINE_VISIBILITY
+    const_reverse_iterator rend() const _NOEXCEPT
+        {return const_reverse_iterator(begin());}
+
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator cbegin()  const _NOEXCEPT {return begin();}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator cend() const _NOEXCEPT {return end();}
+    _LIBCPP_INLINE_VISIBILITY
+    const_reverse_iterator crbegin() const _NOEXCEPT {return rbegin();}
+    _LIBCPP_INLINE_VISIBILITY
+    const_reverse_iterator crend() const _NOEXCEPT {return rend();}
+
+    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
+    bool empty() const _NOEXCEPT {return __tree_.size() == 0;}
+    _LIBCPP_INLINE_VISIBILITY
+    size_type size() const _NOEXCEPT {return __tree_.size();}
+    _LIBCPP_INLINE_VISIBILITY
+    size_type max_size() const _NOEXCEPT {return __tree_.max_size();}
+
+    // modifiers:
+#ifndef _LIBCPP_CXX03_LANG
+    template <class... _Args>
+        _LIBCPP_INLINE_VISIBILITY
+        iterator emplace(_Args&&... __args)
+            {return __tree_.__emplace_multi(_VSTD::forward<_Args>(__args)...);}
+    template <class... _Args>
+        _LIBCPP_INLINE_VISIBILITY
+        iterator emplace_hint(const_iterator __p, _Args&&... __args)
+            {return __tree_.__emplace_hint_multi(__p, _VSTD::forward<_Args>(__args)...);}
+#endif // _LIBCPP_CXX03_LANG
+
+    _LIBCPP_INLINE_VISIBILITY
+    iterator insert(const value_type& __v)
+        {return __tree_.__insert_multi(__v);}
+    _LIBCPP_INLINE_VISIBILITY
+    iterator insert(const_iterator __p, const value_type& __v)
+        {return __tree_.__insert_multi(__p, __v);}
+
+    template <class _InputIterator>
+        _LIBCPP_INLINE_VISIBILITY
+        void insert(_InputIterator __f, _InputIterator __l)
+        {
+            for (const_iterator __e = cend(); __f != __l; ++__f)
+                __tree_.__insert_multi(__e, *__f);
+        }
+
+#ifndef _LIBCPP_CXX03_LANG
+    _LIBCPP_INLINE_VISIBILITY
+    iterator insert(value_type&& __v)
+        {return __tree_.__insert_multi(_VSTD::move(__v));}
+
+    _LIBCPP_INLINE_VISIBILITY
+    iterator insert(const_iterator __p, value_type&& __v)
+        {return __tree_.__insert_multi(__p, _VSTD::move(__v));}
+
+    _LIBCPP_INLINE_VISIBILITY
+    void insert(initializer_list<value_type> __il)
+        {insert(__il.begin(), __il.end());}
+#endif // _LIBCPP_CXX03_LANG
+
+    _LIBCPP_INLINE_VISIBILITY
+    iterator  erase(const_iterator __p) {return __tree_.erase(__p);}
+    _LIBCPP_INLINE_VISIBILITY
+    size_type erase(const key_type& __k) {return __tree_.__erase_multi(__k);}
+    _LIBCPP_INLINE_VISIBILITY
+    iterator  erase(const_iterator __f, const_iterator __l)
+        {return __tree_.erase(__f, __l);}
+    _LIBCPP_INLINE_VISIBILITY
+    void clear() _NOEXCEPT {__tree_.clear();}
+
+#if _LIBCPP_STD_VER > 14
+    _LIBCPP_INLINE_VISIBILITY
+    iterator insert(node_type&& __nh)
+    {
+        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
+            "node_type with incompatible allocator passed to multiset::insert()");
+        return __tree_.template __node_handle_insert_multi<node_type>(
+            _VSTD::move(__nh));
+    }
+    _LIBCPP_INLINE_VISIBILITY
+    iterator insert(const_iterator __hint, node_type&& __nh)
+    {
+        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
+            "node_type with incompatible allocator passed to multiset::insert()");
+        return __tree_.template __node_handle_insert_multi<node_type>(
+            __hint, _VSTD::move(__nh));
+    }
+    _LIBCPP_INLINE_VISIBILITY
+    node_type extract(key_type const& __key)
+    {
+        return __tree_.template __node_handle_extract<node_type>(__key);
+    }
+    _LIBCPP_INLINE_VISIBILITY
+    node_type extract(const_iterator __it)
+    {
+        return __tree_.template __node_handle_extract<node_type>(__it);
+    }
+    template <class _Compare2>
+    _LIBCPP_INLINE_VISIBILITY
+    void merge(multiset<key_type, _Compare2, allocator_type>& __source)
+    {
+        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
+                       "merging container with incompatible allocator");
+        __tree_.__node_handle_merge_multi(__source.__tree_);
+    }
+    template <class _Compare2>
+    _LIBCPP_INLINE_VISIBILITY
+    void merge(multiset<key_type, _Compare2, allocator_type>&& __source)
+    {
+        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
+                       "merging container with incompatible allocator");
+        __tree_.__node_handle_merge_multi(__source.__tree_);
+    }
+    template <class _Compare2>
+    _LIBCPP_INLINE_VISIBILITY
+    void merge(set<key_type, _Compare2, allocator_type>& __source)
+    {
+        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
+                       "merging container with incompatible allocator");
+        __tree_.__node_handle_merge_multi(__source.__tree_);
+    }
+    template <class _Compare2>
+    _LIBCPP_INLINE_VISIBILITY
+    void merge(set<key_type, _Compare2, allocator_type>&& __source)
+    {
+        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
+                       "merging container with incompatible allocator");
+        __tree_.__node_handle_merge_multi(__source.__tree_);
+    }
+#endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    void swap(multiset& __s)
+        _NOEXCEPT_(__is_nothrow_swappable<__base>::value)
+        {__tree_.swap(__s.__tree_);}
+
+    _LIBCPP_INLINE_VISIBILITY
+    allocator_type get_allocator() const _NOEXCEPT {return __tree_.__alloc();}
+    _LIBCPP_INLINE_VISIBILITY
+    key_compare    key_comp()      const {return __tree_.value_comp();}
+    _LIBCPP_INLINE_VISIBILITY
+    value_compare  value_comp()    const {return __tree_.value_comp();}
+
+    // set operations:
+    _LIBCPP_INLINE_VISIBILITY
+    iterator find(const key_type& __k)             {return __tree_.find(__k);}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator find(const key_type& __k) const {return __tree_.find(__k);}
+#if _LIBCPP_STD_VER > 11
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,iterator>::type
+    find(const _K2& __k)                           {return __tree_.find(__k);}
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,const_iterator>::type
+    find(const _K2& __k) const                     {return __tree_.find(__k);}
+#endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    size_type      count(const key_type& __k) const
+        {return __tree_.__count_multi(__k);}
+#if _LIBCPP_STD_VER > 11
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,size_type>::type
+    count(const _K2& __k) const            {return __tree_.__count_multi(__k);}
+#endif
+
+#if _LIBCPP_STD_VER > 17
+    _LIBCPP_INLINE_VISIBILITY
+    bool contains(const key_type& __k) const {return find(__k) != end();}
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value, bool>::type
+    contains(const _K2& __k) const { return find(__k) != end(); }
+#endif // _LIBCPP_STD_VER > 17
+
+    _LIBCPP_INLINE_VISIBILITY
+    iterator lower_bound(const key_type& __k)
+        {return __tree_.lower_bound(__k);}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator lower_bound(const key_type& __k) const
+            {return __tree_.lower_bound(__k);}
+#if _LIBCPP_STD_VER > 11
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,iterator>::type
+    lower_bound(const _K2& __k)       {return __tree_.lower_bound(__k);}
+
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,const_iterator>::type
+    lower_bound(const _K2& __k) const {return __tree_.lower_bound(__k);}
+#endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    iterator upper_bound(const key_type& __k)
+            {return __tree_.upper_bound(__k);}
+    _LIBCPP_INLINE_VISIBILITY
+    const_iterator upper_bound(const key_type& __k) const
+            {return __tree_.upper_bound(__k);}
+#if _LIBCPP_STD_VER > 11
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,iterator>::type
+    upper_bound(const _K2& __k)       {return __tree_.upper_bound(__k);}
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,const_iterator>::type
+    upper_bound(const _K2& __k) const {return __tree_.upper_bound(__k);}
+#endif
+
+    _LIBCPP_INLINE_VISIBILITY
+    pair<iterator,iterator>             equal_range(const key_type& __k)
+            {return __tree_.__equal_range_multi(__k);}
+    _LIBCPP_INLINE_VISIBILITY
+    pair<const_iterator,const_iterator> equal_range(const key_type& __k) const
+            {return __tree_.__equal_range_multi(__k);}
+#if _LIBCPP_STD_VER > 11
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,pair<iterator,iterator>>::type
+    equal_range(const _K2& __k)       {return __tree_.__equal_range_multi(__k);}
+    template <typename _K2>
+    _LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_transparent<_Compare, _K2>::value,pair<const_iterator,const_iterator>>::type
+    equal_range(const _K2& __k) const {return __tree_.__equal_range_multi(__k);}
+#endif
+};
+
+#if _LIBCPP_STD_VER >= 17
+template<class _InputIterator,
+         class _Compare = less<__iter_value_type<_InputIterator>>,
+         class _Allocator = allocator<__iter_value_type<_InputIterator>>,
+         class = enable_if_t<__is_allocator<_Allocator>::value, void>,
+         class = enable_if_t<!__is_allocator<_Compare>::value, void>>
+multiset(_InputIterator, _InputIterator, _Compare = _Compare(), _Allocator = _Allocator())
+  -> multiset<__iter_value_type<_InputIterator>, _Compare, _Allocator>;
+
+template<class _Key, class _Compare = less<_Key>,
+         class _Allocator = allocator<_Key>,
+         class = enable_if_t<__is_allocator<_Allocator>::value, void>,
+         class = enable_if_t<!__is_allocator<_Compare>::value, void>>
+multiset(initializer_list<_Key>, _Compare = _Compare(), _Allocator = _Allocator())
+  -> multiset<_Key, _Compare, _Allocator>;
+
+template<class _InputIterator, class _Allocator,
+         class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+multiset(_InputIterator, _InputIterator, _Allocator)
+  -> multiset<__iter_value_type<_InputIterator>,
+         less<__iter_value_type<_InputIterator>>, _Allocator>;
+
+template<class _Key, class _Allocator,
+         class = enable_if_t<__is_allocator<_Allocator>::value, void>>
+multiset(initializer_list<_Key>, _Allocator)
+  -> multiset<_Key, less<_Key>, _Allocator>;
+#endif
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Compare, class _Allocator>
+multiset<_Key, _Compare, _Allocator>::multiset(multiset&& __s, const allocator_type& __a)
+    : __tree_(_VSTD::move(__s.__tree_), __a)
+{
+    if (__a != __s.get_allocator())
+    {
+        const_iterator __e = cend();
+        while (!__s.empty())
+            insert(__e, _VSTD::move(__s.__tree_.remove(__s.begin())->__value_));
+    }
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator==(const multiset<_Key, _Compare, _Allocator>& __x,
+           const multiset<_Key, _Compare, _Allocator>& __y)
+{
+    return __x.size() == __y.size() && _VSTD::equal(__x.begin(), __x.end(), __y.begin());
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator< (const multiset<_Key, _Compare, _Allocator>& __x,
+           const multiset<_Key, _Compare, _Allocator>& __y)
+{
+    return _VSTD::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator!=(const multiset<_Key, _Compare, _Allocator>& __x,
+           const multiset<_Key, _Compare, _Allocator>& __y)
+{
+    return !(__x == __y);
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator> (const multiset<_Key, _Compare, _Allocator>& __x,
+           const multiset<_Key, _Compare, _Allocator>& __y)
+{
+    return __y < __x;
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator>=(const multiset<_Key, _Compare, _Allocator>& __x,
+           const multiset<_Key, _Compare, _Allocator>& __y)
+{
+    return !(__x < __y);
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+bool
+operator<=(const multiset<_Key, _Compare, _Allocator>& __x,
+           const multiset<_Key, _Compare, _Allocator>& __y)
+{
+    return !(__y < __x);
+}
+
+template <class _Key, class _Compare, class _Allocator>
+inline _LIBCPP_INLINE_VISIBILITY
+void
+swap(multiset<_Key, _Compare, _Allocator>& __x,
+     multiset<_Key, _Compare, _Allocator>& __y)
+    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
+{
+    __x.swap(__y);
+}
+
+#if _LIBCPP_STD_VER > 17
+template <class _Key, class _Compare, class _Allocator, class _Predicate>
+inline _LIBCPP_INLINE_VISIBILITY
+    typename multiset<_Key, _Compare, _Allocator>::size_type
+    erase_if(multiset<_Key, _Compare, _Allocator>& __c, _Predicate __pred) {
+  return _VSTD::__libcpp_erase_if_container(__c, __pred);
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_SET