xref: /llvm-project-15.0.7/libcxx/include/__tree (revision 498ee00a)
1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP___TREE
12#define _LIBCPP___TREE
13
14#include <__config>
15#include <iterator>
16#include <memory>
17#include <stdexcept>
18#include <algorithm>
19
20#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
21#pragma GCC system_header
22#endif
23
24_LIBCPP_BEGIN_NAMESPACE_STD
25
26template <class _Tp, class _Compare, class _Allocator> class __tree;
27template <class _Tp, class _NodePtr, class _DiffType>
28    class _LIBCPP_TYPE_VIS_ONLY __tree_iterator;
29template <class _Tp, class _ConstNodePtr, class _DiffType>
30    class _LIBCPP_TYPE_VIS_ONLY __tree_const_iterator;
31
32template <class _Pointer> class __tree_end_node;
33template <class _VoidPtr> class __tree_node_base;
34template <class _Tp, class _VoidPtr> class __tree_node;
35
36#ifndef _LIBCPP_CXX03_LANG
37template <class _Key, class _Value>
38union __value_type;
39#else
40template <class _Key, class _Value>
41struct __value_type;
42#endif
43
44template <class _Allocator> class __map_node_destructor;
45template <class _TreeIterator> class _LIBCPP_TYPE_VIS_ONLY __map_iterator;
46template <class _TreeIterator> class _LIBCPP_TYPE_VIS_ONLY __map_const_iterator;
47
48/*
49
50_NodePtr algorithms
51
52The algorithms taking _NodePtr are red black tree algorithms.  Those
53algorithms taking a parameter named __root should assume that __root
54points to a proper red black tree (unless otherwise specified).
55
56Each algorithm herein assumes that __root->__parent_ points to a non-null
57structure which has a member __left_ which points back to __root.  No other
58member is read or written to at __root->__parent_.
59
60__root->__parent_ will be referred to below (in comments only) as end_node.
61end_node->__left_ is an externably accessible lvalue for __root, and can be
62changed by node insertion and removal (without explicit reference to end_node).
63
64All nodes (with the exception of end_node), even the node referred to as
65__root, have a non-null __parent_ field.
66
67*/
68
69// Returns:  true if __x is a left child of its parent, else false
70// Precondition:  __x != nullptr.
71template <class _NodePtr>
72inline _LIBCPP_INLINE_VISIBILITY
73bool
74__tree_is_left_child(_NodePtr __x) _NOEXCEPT
75{
76    return __x == __x->__parent_->__left_;
77}
78
79// Determintes if the subtree rooted at __x is a proper red black subtree.  If
80//    __x is a proper subtree, returns the black height (null counts as 1).  If
81//    __x is an improper subtree, returns 0.
82template <class _NodePtr>
83unsigned
84__tree_sub_invariant(_NodePtr __x)
85{
86    if (__x == nullptr)
87        return 1;
88    // parent consistency checked by caller
89    // check __x->__left_ consistency
90    if (__x->__left_ != nullptr && __x->__left_->__parent_ != __x)
91        return 0;
92    // check __x->__right_ consistency
93    if (__x->__right_ != nullptr && __x->__right_->__parent_ != __x)
94        return 0;
95    // check __x->__left_ != __x->__right_ unless both are nullptr
96    if (__x->__left_ == __x->__right_ && __x->__left_ != nullptr)
97        return 0;
98    // If this is red, neither child can be red
99    if (!__x->__is_black_)
100    {
101        if (__x->__left_ && !__x->__left_->__is_black_)
102            return 0;
103        if (__x->__right_ && !__x->__right_->__is_black_)
104            return 0;
105    }
106    unsigned __h = __tree_sub_invariant(__x->__left_);
107    if (__h == 0)
108        return 0;  // invalid left subtree
109    if (__h != __tree_sub_invariant(__x->__right_))
110        return 0;  // invalid or different height right subtree
111    return __h + __x->__is_black_;  // return black height of this node
112}
113
114// Determintes if the red black tree rooted at __root is a proper red black tree.
115//    __root == nullptr is a proper tree.  Returns true is __root is a proper
116//    red black tree, else returns false.
117template <class _NodePtr>
118bool
119__tree_invariant(_NodePtr __root)
120{
121    if (__root == nullptr)
122        return true;
123    // check __x->__parent_ consistency
124    if (__root->__parent_ == nullptr)
125        return false;
126    if (!__tree_is_left_child(__root))
127        return false;
128    // root must be black
129    if (!__root->__is_black_)
130        return false;
131    // do normal node checks
132    return __tree_sub_invariant(__root) != 0;
133}
134
135// Returns:  pointer to the left-most node under __x.
136// Precondition:  __x != nullptr.
137template <class _NodePtr>
138inline _LIBCPP_INLINE_VISIBILITY
139_NodePtr
140__tree_min(_NodePtr __x) _NOEXCEPT
141{
142    while (__x->__left_ != nullptr)
143        __x = __x->__left_;
144    return __x;
145}
146
147// Returns:  pointer to the right-most node under __x.
148// Precondition:  __x != nullptr.
149template <class _NodePtr>
150inline _LIBCPP_INLINE_VISIBILITY
151_NodePtr
152__tree_max(_NodePtr __x) _NOEXCEPT
153{
154    while (__x->__right_ != nullptr)
155        __x = __x->__right_;
156    return __x;
157}
158
159// Returns:  pointer to the next in-order node after __x.
160// Precondition:  __x != nullptr.
161template <class _NodePtr>
162_NodePtr
163__tree_next(_NodePtr __x) _NOEXCEPT
164{
165    if (__x->__right_ != nullptr)
166        return __tree_min(__x->__right_);
167    while (!__tree_is_left_child(__x))
168        __x = __x->__parent_unsafe();
169    return __x->__parent_unsafe();
170}
171
172template <class _EndNodePtr, class _NodePtr>
173inline _LIBCPP_INLINE_VISIBILITY
174_EndNodePtr
175__tree_next_iter(_NodePtr __x) _NOEXCEPT
176{
177    if (__x->__right_ != nullptr)
178        return static_cast<_EndNodePtr>(__tree_min(__x->__right_));
179    while (!__tree_is_left_child(__x))
180        __x = __x->__parent_unsafe();
181    return static_cast<_EndNodePtr>(__x->__parent_);
182}
183
184// Returns:  pointer to the previous in-order node before __x.
185// Precondition:  __x != nullptr.
186// Note: __x may be the end node.
187template <class _NodePtr, class _EndNodePtr>
188inline _LIBCPP_INLINE_VISIBILITY
189_NodePtr
190__tree_prev_iter(_EndNodePtr __x) _NOEXCEPT
191{
192    if (__x->__left_ != nullptr)
193        return __tree_max(__x->__left_);
194    _NodePtr __xx = static_cast<_NodePtr>(__x);
195    while (__tree_is_left_child(__xx))
196        __xx = __xx->__parent_unsafe();
197    return __xx->__parent_unsafe();
198}
199
200// Returns:  pointer to a node which has no children
201// Precondition:  __x != nullptr.
202template <class _NodePtr>
203_NodePtr
204__tree_leaf(_NodePtr __x) _NOEXCEPT
205{
206    while (true)
207    {
208        if (__x->__left_ != nullptr)
209        {
210            __x = __x->__left_;
211            continue;
212        }
213        if (__x->__right_ != nullptr)
214        {
215            __x = __x->__right_;
216            continue;
217        }
218        break;
219    }
220    return __x;
221}
222
223// Effects:  Makes __x->__right_ the subtree root with __x as its left child
224//           while preserving in-order order.
225// Precondition:  __x->__right_ != nullptr
226template <class _NodePtr>
227void
228__tree_left_rotate(_NodePtr __x) _NOEXCEPT
229{
230    _NodePtr __y = __x->__right_;
231    __x->__right_ = __y->__left_;
232    if (__x->__right_ != nullptr)
233        __x->__right_->__set_parent(__x);
234    __y->__parent_ = __x->__parent_;
235    if (__tree_is_left_child(__x))
236        __x->__parent_->__left_ = __y;
237    else
238        __x->__parent_unsafe()->__right_ = __y;
239    __y->__left_ = __x;
240    __x->__set_parent(__y);
241}
242
243// Effects:  Makes __x->__left_ the subtree root with __x as its right child
244//           while preserving in-order order.
245// Precondition:  __x->__left_ != nullptr
246template <class _NodePtr>
247void
248__tree_right_rotate(_NodePtr __x) _NOEXCEPT
249{
250    _NodePtr __y = __x->__left_;
251    __x->__left_ = __y->__right_;
252    if (__x->__left_ != nullptr)
253        __x->__left_->__set_parent(__x);
254    __y->__parent_ = __x->__parent_;
255    if (__tree_is_left_child(__x))
256        __x->__parent_->__left_ = __y;
257    else
258        __x->__parent_unsafe()->__right_ = __y;
259    __y->__right_ = __x;
260    __x->__set_parent(__y);
261}
262
263// Effects:  Rebalances __root after attaching __x to a leaf.
264// Precondition:  __root != nulptr && __x != nullptr.
265//                __x has no children.
266//                __x == __root or == a direct or indirect child of __root.
267//                If __x were to be unlinked from __root (setting __root to
268//                  nullptr if __root == __x), __tree_invariant(__root) == true.
269// Postcondition: __tree_invariant(end_node->__left_) == true.  end_node->__left_
270//                may be different than the value passed in as __root.
271template <class _NodePtr>
272void
273__tree_balance_after_insert(_NodePtr __root, _NodePtr __x) _NOEXCEPT
274{
275    __x->__is_black_ = __x == __root;
276    while (__x != __root && !__x->__parent_unsafe()->__is_black_)
277    {
278        // __x->__parent_ != __root because __x->__parent_->__is_black == false
279        if (__tree_is_left_child(__x->__parent_unsafe()))
280        {
281            _NodePtr __y = __x->__parent_unsafe()->__parent_unsafe()->__right_;
282            if (__y != nullptr && !__y->__is_black_)
283            {
284                __x = __x->__parent_unsafe();
285                __x->__is_black_ = true;
286                __x = __x->__parent_unsafe();
287                __x->__is_black_ = __x == __root;
288                __y->__is_black_ = true;
289            }
290            else
291            {
292                if (!__tree_is_left_child(__x))
293                {
294                    __x = __x->__parent_unsafe();
295                    __tree_left_rotate(__x);
296                }
297                __x = __x->__parent_unsafe();
298                __x->__is_black_ = true;
299                __x = __x->__parent_unsafe();
300                __x->__is_black_ = false;
301                __tree_right_rotate(__x);
302                break;
303            }
304        }
305        else
306        {
307            _NodePtr __y = __x->__parent_unsafe()->__parent_->__left_;
308            if (__y != nullptr && !__y->__is_black_)
309            {
310                __x = __x->__parent_unsafe();
311                __x->__is_black_ = true;
312                __x = __x->__parent_unsafe();
313                __x->__is_black_ = __x == __root;
314                __y->__is_black_ = true;
315            }
316            else
317            {
318                if (__tree_is_left_child(__x))
319                {
320                    __x = __x->__parent_unsafe();
321                    __tree_right_rotate(__x);
322                }
323                __x = __x->__parent_unsafe();
324                __x->__is_black_ = true;
325                __x = __x->__parent_unsafe();
326                __x->__is_black_ = false;
327                __tree_left_rotate(__x);
328                break;
329            }
330        }
331    }
332}
333
334// Precondition:  __root != nullptr && __z != nullptr.
335//                __tree_invariant(__root) == true.
336//                __z == __root or == a direct or indirect child of __root.
337// Effects:  unlinks __z from the tree rooted at __root, rebalancing as needed.
338// Postcondition: __tree_invariant(end_node->__left_) == true && end_node->__left_
339//                nor any of its children refer to __z.  end_node->__left_
340//                may be different than the value passed in as __root.
341template <class _NodePtr>
342void
343__tree_remove(_NodePtr __root, _NodePtr __z) _NOEXCEPT
344{
345    // __z will be removed from the tree.  Client still needs to destruct/deallocate it
346    // __y is either __z, or if __z has two children, __tree_next(__z).
347    // __y will have at most one child.
348    // __y will be the initial hole in the tree (make the hole at a leaf)
349    _NodePtr __y = (__z->__left_ == nullptr || __z->__right_ == nullptr) ?
350                    __z : __tree_next(__z);
351    // __x is __y's possibly null single child
352    _NodePtr __x = __y->__left_ != nullptr ? __y->__left_ : __y->__right_;
353    // __w is __x's possibly null uncle (will become __x's sibling)
354    _NodePtr __w = nullptr;
355    // link __x to __y's parent, and find __w
356    if (__x != nullptr)
357        __x->__parent_ = __y->__parent_;
358    if (__tree_is_left_child(__y))
359    {
360        __y->__parent_->__left_ = __x;
361        if (__y != __root)
362            __w = __y->__parent_unsafe()->__right_;
363        else
364            __root = __x;  // __w == nullptr
365    }
366    else
367    {
368        __y->__parent_unsafe()->__right_ = __x;
369        // __y can't be root if it is a right child
370        __w = __y->__parent_->__left_;
371    }
372    bool __removed_black = __y->__is_black_;
373    // If we didn't remove __z, do so now by splicing in __y for __z,
374    //    but copy __z's color.  This does not impact __x or __w.
375    if (__y != __z)
376    {
377        // __z->__left_ != nulptr but __z->__right_ might == __x == nullptr
378        __y->__parent_ = __z->__parent_;
379        if (__tree_is_left_child(__z))
380            __y->__parent_->__left_ = __y;
381        else
382            __y->__parent_unsafe()->__right_ = __y;
383        __y->__left_ = __z->__left_;
384        __y->__left_->__set_parent(__y);
385        __y->__right_ = __z->__right_;
386        if (__y->__right_ != nullptr)
387            __y->__right_->__set_parent(__y);
388        __y->__is_black_ = __z->__is_black_;
389        if (__root == __z)
390            __root = __y;
391    }
392    // There is no need to rebalance if we removed a red, or if we removed
393    //     the last node.
394    if (__removed_black && __root != nullptr)
395    {
396        // Rebalance:
397        // __x has an implicit black color (transferred from the removed __y)
398        //    associated with it, no matter what its color is.
399        // If __x is __root (in which case it can't be null), it is supposed
400        //    to be black anyway, and if it is doubly black, then the double
401        //    can just be ignored.
402        // If __x is red (in which case it can't be null), then it can absorb
403        //    the implicit black just by setting its color to black.
404        // Since __y was black and only had one child (which __x points to), __x
405        //   is either red with no children, else null, otherwise __y would have
406        //   different black heights under left and right pointers.
407        // if (__x == __root || __x != nullptr && !__x->__is_black_)
408        if (__x != nullptr)
409            __x->__is_black_ = true;
410        else
411        {
412            //  Else __x isn't root, and is "doubly black", even though it may
413            //     be null.  __w can not be null here, else the parent would
414            //     see a black height >= 2 on the __x side and a black height
415            //     of 1 on the __w side (__w must be a non-null black or a red
416            //     with a non-null black child).
417            while (true)
418            {
419                if (!__tree_is_left_child(__w))  // if x is left child
420                {
421                    if (!__w->__is_black_)
422                    {
423                        __w->__is_black_ = true;
424                        __w->__parent_unsafe()->__is_black_ = false;
425                        __tree_left_rotate(__w->__parent_unsafe());
426                        // __x is still valid
427                        // reset __root only if necessary
428                        if (__root == __w->__left_)
429                            __root = __w;
430                        // reset sibling, and it still can't be null
431                        __w = __w->__left_->__right_;
432                    }
433                    // __w->__is_black_ is now true, __w may have null children
434                    if ((__w->__left_  == nullptr || __w->__left_->__is_black_) &&
435                        (__w->__right_ == nullptr || __w->__right_->__is_black_))
436                    {
437                        __w->__is_black_ = false;
438                        __x = __w->__parent_unsafe();
439                        // __x can no longer be null
440                        if (__x == __root || !__x->__is_black_)
441                        {
442                            __x->__is_black_ = true;
443                            break;
444                        }
445                        // reset sibling, and it still can't be null
446                        __w = __tree_is_left_child(__x) ?
447                                    __x->__parent_unsafe()->__right_ :
448                                    __x->__parent_->__left_;
449                        // continue;
450                    }
451                    else  // __w has a red child
452                    {
453                        if (__w->__right_ == nullptr || __w->__right_->__is_black_)
454                        {
455                            // __w left child is non-null and red
456                            __w->__left_->__is_black_ = true;
457                            __w->__is_black_ = false;
458                            __tree_right_rotate(__w);
459                            // __w is known not to be root, so root hasn't changed
460                            // reset sibling, and it still can't be null
461                            __w = __w->__parent_unsafe();
462                        }
463                        // __w has a right red child, left child may be null
464                        __w->__is_black_ = __w->__parent_unsafe()->__is_black_;
465                        __w->__parent_unsafe()->__is_black_ = true;
466                        __w->__right_->__is_black_ = true;
467                        __tree_left_rotate(__w->__parent_unsafe());
468                        break;
469                    }
470                }
471                else
472                {
473                    if (!__w->__is_black_)
474                    {
475                        __w->__is_black_ = true;
476                        __w->__parent_unsafe()->__is_black_ = false;
477                        __tree_right_rotate(__w->__parent_unsafe());
478                        // __x is still valid
479                        // reset __root only if necessary
480                        if (__root == __w->__right_)
481                            __root = __w;
482                        // reset sibling, and it still can't be null
483                        __w = __w->__right_->__left_;
484                    }
485                    // __w->__is_black_ is now true, __w may have null children
486                    if ((__w->__left_  == nullptr || __w->__left_->__is_black_) &&
487                        (__w->__right_ == nullptr || __w->__right_->__is_black_))
488                    {
489                        __w->__is_black_ = false;
490                        __x = __w->__parent_unsafe();
491                        // __x can no longer be null
492                        if (!__x->__is_black_ || __x == __root)
493                        {
494                            __x->__is_black_ = true;
495                            break;
496                        }
497                        // reset sibling, and it still can't be null
498                        __w = __tree_is_left_child(__x) ?
499                                    __x->__parent_unsafe()->__right_ :
500                                    __x->__parent_->__left_;
501                        // continue;
502                    }
503                    else  // __w has a red child
504                    {
505                        if (__w->__left_ == nullptr || __w->__left_->__is_black_)
506                        {
507                            // __w right child is non-null and red
508                            __w->__right_->__is_black_ = true;
509                            __w->__is_black_ = false;
510                            __tree_left_rotate(__w);
511                            // __w is known not to be root, so root hasn't changed
512                            // reset sibling, and it still can't be null
513                            __w = __w->__parent_unsafe();
514                        }
515                        // __w has a left red child, right child may be null
516                        __w->__is_black_ = __w->__parent_unsafe()->__is_black_;
517                        __w->__parent_unsafe()->__is_black_ = true;
518                        __w->__left_->__is_black_ = true;
519                        __tree_right_rotate(__w->__parent_unsafe());
520                        break;
521                    }
522                }
523            }
524        }
525    }
526}
527
528// node traits
529
530
531#ifndef _LIBCPP_CXX03_LANG
532template <class _Tp>
533struct __is_tree_value_type_imp : false_type {};
534
535template <class _Key, class _Value>
536struct __is_tree_value_type_imp<__value_type<_Key, _Value>> : true_type {};
537
538template <class ..._Args>
539struct __is_tree_value_type : false_type {};
540
541template <class _One>
542struct __is_tree_value_type<_One> : __is_tree_value_type_imp<typename __uncvref<_One>::type> {};
543#endif
544
545template <class _Tp>
546struct __tree_key_value_types {
547  typedef _Tp key_type;
548  typedef _Tp __node_value_type;
549  typedef _Tp __container_value_type;
550  static const bool __is_map = false;
551
552  _LIBCPP_INLINE_VISIBILITY
553  static key_type const& __get_key(_Tp const& __v) {
554    return __v;
555  }
556  _LIBCPP_INLINE_VISIBILITY
557  static __container_value_type const& __get_value(__node_value_type const& __v) {
558    return __v;
559  }
560  _LIBCPP_INLINE_VISIBILITY
561  static __container_value_type* __get_ptr(__node_value_type& __n) {
562    return _VSTD::addressof(__n);
563  }
564
565#ifndef _LIBCPP_CXX03_LANG
566  _LIBCPP_INLINE_VISIBILITY
567  static  __container_value_type&& __move(__node_value_type& __v) {
568    return _VSTD::move(__v);
569  }
570#endif
571};
572
573template <class _Key, class _Tp>
574struct __tree_key_value_types<__value_type<_Key, _Tp> > {
575  typedef _Key                                         key_type;
576  typedef _Tp                                          mapped_type;
577  typedef __value_type<_Key, _Tp>                      __node_value_type;
578  typedef pair<const _Key, _Tp>                        __container_value_type;
579  typedef pair<_Key, _Tp>                              __nc_value_type;
580  typedef __container_value_type                       __map_value_type;
581  static const bool __is_map = true;
582
583  _LIBCPP_INLINE_VISIBILITY
584  static key_type const&
585  __get_key(__node_value_type const& __t) {
586    return __t.__cc.first;
587  }
588
589  template <class _Up>
590  _LIBCPP_INLINE_VISIBILITY
591  static typename enable_if<__is_same_uncvref<_Up, __container_value_type>::value,
592      key_type const&>::type
593  __get_key(_Up& __t) {
594    return __t.first;
595  }
596
597  _LIBCPP_INLINE_VISIBILITY
598  static __container_value_type const&
599  __get_value(__node_value_type const& __t) {
600    return __t.__cc;
601  }
602
603  template <class _Up>
604  _LIBCPP_INLINE_VISIBILITY
605  static typename enable_if<__is_same_uncvref<_Up, __container_value_type>::value,
606      __container_value_type const&>::type
607  __get_value(_Up& __t) {
608    return __t;
609  }
610
611  _LIBCPP_INLINE_VISIBILITY
612  static __container_value_type* __get_ptr(__node_value_type& __n) {
613    return _VSTD::addressof(__n.__cc);
614  }
615
616#ifndef _LIBCPP_CXX03_LANG
617  _LIBCPP_INLINE_VISIBILITY
618  static  __nc_value_type&& __move(__node_value_type& __v) {
619    return _VSTD::move(__v.__nc);
620  }
621#endif
622};
623
624template <class _VoidPtr>
625struct __tree_node_base_types {
626  typedef _VoidPtr                                               __void_pointer;
627
628  typedef __tree_node_base<__void_pointer>                      __node_base_type;
629  typedef typename __rebind_pointer<_VoidPtr, __node_base_type>::type
630                                                             __node_base_pointer;
631
632  typedef __tree_end_node<__node_base_pointer>                  __end_node_type;
633  typedef typename __rebind_pointer<_VoidPtr, __end_node_type>::type
634                                                             __end_node_pointer;
635#if defined(_LIBCPP_ABI_TREE_REMOVE_NODE_POINTER_UB)
636  typedef __end_node_pointer __parent_pointer;
637#else
638  typedef typename conditional<
639      is_pointer<__end_node_pointer>::value,
640        __end_node_pointer,
641        __node_base_pointer>::type __parent_pointer;
642#endif
643
644private:
645  static_assert((is_same<typename pointer_traits<_VoidPtr>::element_type, void>::value),
646                  "_VoidPtr does not point to unqualified void type");
647};
648
649template <class _Tp, class _AllocPtr, class _KVTypes = __tree_key_value_types<_Tp>,
650         bool = _KVTypes::__is_map>
651struct __tree_map_pointer_types {};
652
653template <class _Tp, class _AllocPtr, class _KVTypes>
654struct __tree_map_pointer_types<_Tp, _AllocPtr, _KVTypes, true> {
655  typedef typename _KVTypes::__map_value_type   _Mv;
656  typedef typename __rebind_pointer<_AllocPtr, _Mv>::type
657                                                       __map_value_type_pointer;
658  typedef typename __rebind_pointer<_AllocPtr, const _Mv>::type
659                                                 __const_map_value_type_pointer;
660};
661
662template <class _NodePtr, class _NodeT = typename pointer_traits<_NodePtr>::element_type>
663struct __tree_node_types;
664
665template <class _NodePtr, class _Tp, class _VoidPtr>
666struct __tree_node_types<_NodePtr, __tree_node<_Tp, _VoidPtr> >
667    : public __tree_node_base_types<_VoidPtr>,
668             __tree_key_value_types<_Tp>,
669             __tree_map_pointer_types<_Tp, _VoidPtr>
670{
671  typedef __tree_node_base_types<_VoidPtr> __base;
672  typedef __tree_key_value_types<_Tp>      __key_base;
673  typedef __tree_map_pointer_types<_Tp, _VoidPtr> __map_pointer_base;
674public:
675
676  typedef typename pointer_traits<_NodePtr>::element_type       __node_type;
677  typedef _NodePtr                                              __node_pointer;
678
679  typedef _Tp                                                 __node_value_type;
680  typedef typename __rebind_pointer<_VoidPtr, __node_value_type>::type
681                                                      __node_value_type_pointer;
682  typedef typename __rebind_pointer<_VoidPtr, const __node_value_type>::type
683                                                __const_node_value_type_pointer;
684#if defined(_LIBCPP_ABI_TREE_REMOVE_NODE_POINTER_UB)
685  typedef typename __base::__end_node_pointer __iter_pointer;
686#else
687  typedef typename conditional<
688      is_pointer<__node_pointer>::value,
689        typename __base::__end_node_pointer,
690        __node_pointer>::type __iter_pointer;
691#endif
692private:
693    static_assert(!is_const<__node_type>::value,
694                "_NodePtr should never be a pointer to const");
695    static_assert((is_same<typename __rebind_pointer<_VoidPtr, __node_type>::type,
696                          _NodePtr>::value), "_VoidPtr does not rebind to _NodePtr.");
697};
698
699template <class _ValueTp, class _VoidPtr>
700struct __make_tree_node_types {
701  typedef typename __rebind_pointer<_VoidPtr, __tree_node<_ValueTp, _VoidPtr> >::type
702                                                                        _NodePtr;
703  typedef __tree_node_types<_NodePtr> type;
704};
705
706// node
707
708template <class _Pointer>
709class __tree_end_node
710{
711public:
712    typedef _Pointer pointer;
713    pointer __left_;
714
715    _LIBCPP_INLINE_VISIBILITY
716    __tree_end_node() _NOEXCEPT : __left_() {}
717};
718
719template <class _VoidPtr>
720class __tree_node_base
721    : public __tree_node_base_types<_VoidPtr>::__end_node_type
722{
723    typedef __tree_node_base_types<_VoidPtr> _NodeBaseTypes;
724
725public:
726    typedef typename _NodeBaseTypes::__node_base_pointer pointer;
727    typedef typename _NodeBaseTypes::__parent_pointer __parent_pointer;
728
729    pointer          __right_;
730    __parent_pointer __parent_;
731    bool __is_black_;
732
733    _LIBCPP_INLINE_VISIBILITY
734    pointer __parent_unsafe() const { return static_cast<pointer>(__parent_);}
735
736    _LIBCPP_INLINE_VISIBILITY
737    void __set_parent(pointer __p) {
738        __parent_ = static_cast<__parent_pointer>(__p);
739    }
740
741private:
742  ~__tree_node_base() _LIBCPP_EQUAL_DELETE;
743  __tree_node_base(__tree_node_base const&) _LIBCPP_EQUAL_DELETE;
744  __tree_node_base& operator=(__tree_node_base const&) _LIBCPP_EQUAL_DELETE;
745};
746
747template <class _Tp, class _VoidPtr>
748class __tree_node
749    : public __tree_node_base<_VoidPtr>
750{
751public:
752    typedef _Tp __node_value_type;
753
754    __node_value_type __value_;
755
756private:
757  ~__tree_node() _LIBCPP_EQUAL_DELETE;
758  __tree_node(__tree_node const&) _LIBCPP_EQUAL_DELETE;
759  __tree_node& operator=(__tree_node const&) _LIBCPP_EQUAL_DELETE;
760};
761
762
763template <class _Allocator>
764class __tree_node_destructor
765{
766    typedef _Allocator                                      allocator_type;
767    typedef allocator_traits<allocator_type>                __alloc_traits;
768
769public:
770    typedef typename __alloc_traits::pointer                pointer;
771private:
772    typedef __tree_node_types<pointer> _NodeTypes;
773    allocator_type& __na_;
774
775    __tree_node_destructor& operator=(const __tree_node_destructor&);
776
777public:
778    bool __value_constructed;
779
780    _LIBCPP_INLINE_VISIBILITY
781    explicit __tree_node_destructor(allocator_type& __na, bool __val = false) _NOEXCEPT
782        : __na_(__na),
783          __value_constructed(__val)
784        {}
785
786    _LIBCPP_INLINE_VISIBILITY
787    void operator()(pointer __p) _NOEXCEPT
788    {
789        if (__value_constructed)
790            __alloc_traits::destroy(__na_, _NodeTypes::__get_ptr(__p->__value_));
791        if (__p)
792            __alloc_traits::deallocate(__na_, __p, 1);
793    }
794
795    template <class> friend class __map_node_destructor;
796};
797
798
799template <class _Tp, class _NodePtr, class _DiffType>
800class _LIBCPP_TYPE_VIS_ONLY __tree_iterator
801{
802    typedef __tree_node_types<_NodePtr>                     _NodeTypes;
803    typedef _NodePtr                                        __node_pointer;
804    typedef typename _NodeTypes::__node_base_pointer        __node_base_pointer;
805    typedef typename _NodeTypes::__end_node_pointer         __end_node_pointer;
806    typedef typename _NodeTypes::__iter_pointer             __iter_pointer;
807    typedef pointer_traits<__node_pointer> __pointer_traits;
808
809    __iter_pointer __ptr_;
810
811public:
812    typedef bidirectional_iterator_tag                     iterator_category;
813    typedef _Tp                                            value_type;
814    typedef _DiffType                                      difference_type;
815    typedef value_type&                                    reference;
816    typedef typename _NodeTypes::__node_value_type_pointer pointer;
817
818    _LIBCPP_INLINE_VISIBILITY __tree_iterator() _NOEXCEPT
819#if _LIBCPP_STD_VER > 11
820    : __ptr_(nullptr)
821#endif
822    {}
823
824    _LIBCPP_INLINE_VISIBILITY reference operator*() const
825        {return __get_np()->__value_;}
826    _LIBCPP_INLINE_VISIBILITY pointer operator->() const
827        {return pointer_traits<pointer>::pointer_to(__get_np()->__value_);}
828
829    _LIBCPP_INLINE_VISIBILITY
830    __tree_iterator& operator++() {
831      __ptr_ = static_cast<__iter_pointer>(
832          __tree_next_iter<__end_node_pointer>(static_cast<__node_base_pointer>(__ptr_)));
833      return *this;
834    }
835    _LIBCPP_INLINE_VISIBILITY
836    __tree_iterator operator++(int)
837        {__tree_iterator __t(*this); ++(*this); return __t;}
838
839    _LIBCPP_INLINE_VISIBILITY
840    __tree_iterator& operator--() {
841      __ptr_ = static_cast<__iter_pointer>(__tree_prev_iter<__node_base_pointer>(
842          static_cast<__end_node_pointer>(__ptr_)));
843      return *this;
844    }
845    _LIBCPP_INLINE_VISIBILITY
846    __tree_iterator operator--(int)
847        {__tree_iterator __t(*this); --(*this); return __t;}
848
849    friend _LIBCPP_INLINE_VISIBILITY
850        bool operator==(const __tree_iterator& __x, const __tree_iterator& __y)
851        {return __x.__ptr_ == __y.__ptr_;}
852    friend _LIBCPP_INLINE_VISIBILITY
853        bool operator!=(const __tree_iterator& __x, const __tree_iterator& __y)
854        {return !(__x == __y);}
855
856private:
857    _LIBCPP_INLINE_VISIBILITY
858    explicit __tree_iterator(__node_pointer __p) _NOEXCEPT : __ptr_(__p) {}
859    _LIBCPP_INLINE_VISIBILITY
860    explicit __tree_iterator(__end_node_pointer __p) _NOEXCEPT : __ptr_(__p) {}
861    _LIBCPP_INLINE_VISIBILITY
862    __node_pointer __get_np() const { return static_cast<__node_pointer>(__ptr_); }
863    template <class, class, class> friend class __tree;
864    template <class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY __tree_const_iterator;
865    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __map_iterator;
866    template <class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY map;
867    template <class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY multimap;
868    template <class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY set;
869    template <class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY multiset;
870};
871
872template <class _Tp, class _NodePtr, class _DiffType>
873class _LIBCPP_TYPE_VIS_ONLY __tree_const_iterator
874{
875    typedef __tree_node_types<_NodePtr>                     _NodeTypes;
876    typedef typename _NodeTypes::__node_pointer             __node_pointer;
877    typedef typename _NodeTypes::__node_base_pointer        __node_base_pointer;
878    typedef typename _NodeTypes::__end_node_pointer         __end_node_pointer;
879    typedef typename _NodeTypes::__iter_pointer             __iter_pointer;
880    typedef pointer_traits<__node_pointer> __pointer_traits;
881
882    __iter_pointer __ptr_;
883
884public:
885    typedef bidirectional_iterator_tag                           iterator_category;
886    typedef _Tp                                                  value_type;
887    typedef _DiffType                                            difference_type;
888    typedef const value_type&                                    reference;
889    typedef typename _NodeTypes::__const_node_value_type_pointer pointer;
890
891    _LIBCPP_INLINE_VISIBILITY __tree_const_iterator() _NOEXCEPT
892#if _LIBCPP_STD_VER > 11
893    : __ptr_(nullptr)
894#endif
895    {}
896
897private:
898    typedef __tree_iterator<value_type, __node_pointer, difference_type>
899                                                           __non_const_iterator;
900public:
901    _LIBCPP_INLINE_VISIBILITY
902    __tree_const_iterator(__non_const_iterator __p) _NOEXCEPT
903        : __ptr_(__p.__ptr_) {}
904
905    _LIBCPP_INLINE_VISIBILITY reference operator*() const
906        {return __get_np()->__value_;}
907    _LIBCPP_INLINE_VISIBILITY pointer operator->() const
908        {return pointer_traits<pointer>::pointer_to(__get_np()->__value_);}
909
910    _LIBCPP_INLINE_VISIBILITY
911    __tree_const_iterator& operator++() {
912      __ptr_ = static_cast<__iter_pointer>(
913          __tree_next_iter<__end_node_pointer>(static_cast<__node_base_pointer>(__ptr_)));
914      return *this;
915    }
916
917    _LIBCPP_INLINE_VISIBILITY
918    __tree_const_iterator operator++(int)
919        {__tree_const_iterator __t(*this); ++(*this); return __t;}
920
921    _LIBCPP_INLINE_VISIBILITY
922    __tree_const_iterator& operator--() {
923      __ptr_ = static_cast<__iter_pointer>(__tree_prev_iter<__node_base_pointer>(
924          static_cast<__end_node_pointer>(__ptr_)));
925      return *this;
926    }
927
928    _LIBCPP_INLINE_VISIBILITY
929    __tree_const_iterator operator--(int)
930        {__tree_const_iterator __t(*this); --(*this); return __t;}
931
932    friend _LIBCPP_INLINE_VISIBILITY
933        bool operator==(const __tree_const_iterator& __x, const __tree_const_iterator& __y)
934        {return __x.__ptr_ == __y.__ptr_;}
935    friend _LIBCPP_INLINE_VISIBILITY
936        bool operator!=(const __tree_const_iterator& __x, const __tree_const_iterator& __y)
937        {return !(__x == __y);}
938
939private:
940    _LIBCPP_INLINE_VISIBILITY
941    explicit __tree_const_iterator(__node_pointer __p) _NOEXCEPT
942        : __ptr_(__p) {}
943    _LIBCPP_INLINE_VISIBILITY
944    explicit __tree_const_iterator(__end_node_pointer __p) _NOEXCEPT
945        : __ptr_(__p) {}
946    _LIBCPP_INLINE_VISIBILITY
947    __node_pointer __get_np() const { return static_cast<__node_pointer>(__ptr_); }
948
949    template <class, class, class> friend class __tree;
950    template <class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY map;
951    template <class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY multimap;
952    template <class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY set;
953    template <class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY multiset;
954    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __map_const_iterator;
955
956};
957
958template <class _Tp, class _Compare, class _Allocator>
959class __tree
960{
961public:
962    typedef _Tp                                      value_type;
963    typedef _Compare                                 value_compare;
964    typedef _Allocator                               allocator_type;
965
966private:
967    typedef allocator_traits<allocator_type>         __alloc_traits;
968    typedef typename __make_tree_node_types<value_type,
969        typename __alloc_traits::void_pointer>::type
970                                                    _NodeTypes;
971    typedef typename _NodeTypes::key_type           key_type;
972public:
973    typedef typename _NodeTypes::__node_value_type      __node_value_type;
974    typedef typename _NodeTypes::__container_value_type __container_value_type;
975
976    typedef typename __alloc_traits::pointer         pointer;
977    typedef typename __alloc_traits::const_pointer   const_pointer;
978    typedef typename __alloc_traits::size_type       size_type;
979    typedef typename __alloc_traits::difference_type difference_type;
980
981public:
982    typedef typename _NodeTypes::__void_pointer        __void_pointer;
983
984    typedef typename _NodeTypes::__node_type           __node;
985    typedef typename _NodeTypes::__node_pointer        __node_pointer;
986
987    typedef typename _NodeTypes::__node_base_type      __node_base;
988    typedef typename _NodeTypes::__node_base_pointer   __node_base_pointer;
989
990    typedef typename _NodeTypes::__end_node_type       __end_node_t;
991    typedef typename _NodeTypes::__end_node_pointer    __end_node_ptr;
992
993    typedef typename _NodeTypes::__parent_pointer      __parent_pointer;
994    typedef typename _NodeTypes::__iter_pointer        __iter_pointer;
995
996    typedef typename __rebind_alloc_helper<__alloc_traits, __node>::type __node_allocator;
997    typedef allocator_traits<__node_allocator>         __node_traits;
998
999private:
1000    // check for sane allocator pointer rebinding semantics. Rebinding the
1001    // allocator for a new pointer type should be exactly the same as rebinding
1002    // the pointer using 'pointer_traits'.
1003    static_assert((is_same<__node_pointer, typename __node_traits::pointer>::value),
1004                  "Allocator does not rebind pointers in a sane manner.");
1005    typedef typename __rebind_alloc_helper<__node_traits, __node_base>::type
1006        __node_base_allocator;
1007    typedef allocator_traits<__node_base_allocator> __node_base_traits;
1008    static_assert((is_same<__node_base_pointer, typename __node_base_traits::pointer>::value),
1009                 "Allocator does not rebind pointers in a sane manner.");
1010
1011private:
1012    __iter_pointer                                     __begin_node_;
1013    __compressed_pair<__end_node_t, __node_allocator>  __pair1_;
1014    __compressed_pair<size_type, value_compare>        __pair3_;
1015
1016public:
1017    _LIBCPP_INLINE_VISIBILITY
1018    __iter_pointer __end_node() _NOEXCEPT
1019    {
1020        return static_cast<__iter_pointer>(
1021                pointer_traits<__end_node_ptr>::pointer_to(__pair1_.first())
1022        );
1023    }
1024    _LIBCPP_INLINE_VISIBILITY
1025    __iter_pointer __end_node() const _NOEXCEPT
1026    {
1027        return static_cast<__iter_pointer>(
1028            pointer_traits<__end_node_ptr>::pointer_to(
1029                const_cast<__end_node_t&>(__pair1_.first())
1030            )
1031        );
1032    }
1033    _LIBCPP_INLINE_VISIBILITY
1034          __node_allocator& __node_alloc() _NOEXCEPT {return __pair1_.second();}
1035private:
1036    _LIBCPP_INLINE_VISIBILITY
1037    const __node_allocator& __node_alloc() const _NOEXCEPT
1038        {return __pair1_.second();}
1039    _LIBCPP_INLINE_VISIBILITY
1040          __iter_pointer& __begin_node() _NOEXCEPT {return __begin_node_;}
1041    _LIBCPP_INLINE_VISIBILITY
1042    const __iter_pointer& __begin_node() const _NOEXCEPT {return __begin_node_;}
1043public:
1044    _LIBCPP_INLINE_VISIBILITY
1045    allocator_type __alloc() const _NOEXCEPT
1046        {return allocator_type(__node_alloc());}
1047private:
1048    _LIBCPP_INLINE_VISIBILITY
1049          size_type& size() _NOEXCEPT {return __pair3_.first();}
1050public:
1051    _LIBCPP_INLINE_VISIBILITY
1052    const size_type& size() const _NOEXCEPT {return __pair3_.first();}
1053    _LIBCPP_INLINE_VISIBILITY
1054          value_compare& value_comp() _NOEXCEPT {return __pair3_.second();}
1055    _LIBCPP_INLINE_VISIBILITY
1056    const value_compare& value_comp() const _NOEXCEPT
1057        {return __pair3_.second();}
1058public:
1059
1060    _LIBCPP_INLINE_VISIBILITY
1061    __node_pointer __root() const _NOEXCEPT
1062        {return static_cast<__node_pointer>(__end_node()->__left_);}
1063
1064    __node_base_pointer* __root_ptr() const _NOEXCEPT {
1065        return _VSTD::addressof(__end_node()->__left_);
1066    }
1067
1068    typedef __tree_iterator<value_type, __node_pointer, difference_type>             iterator;
1069    typedef __tree_const_iterator<value_type, __node_pointer, difference_type> const_iterator;
1070
1071    explicit __tree(const value_compare& __comp)
1072        _NOEXCEPT_(
1073            is_nothrow_default_constructible<__node_allocator>::value &&
1074            is_nothrow_copy_constructible<value_compare>::value);
1075    explicit __tree(const allocator_type& __a);
1076    __tree(const value_compare& __comp, const allocator_type& __a);
1077    __tree(const __tree& __t);
1078    __tree& operator=(const __tree& __t);
1079    template <class _InputIterator>
1080        void __assign_unique(_InputIterator __first, _InputIterator __last);
1081    template <class _InputIterator>
1082        void __assign_multi(_InputIterator __first, _InputIterator __last);
1083#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1084    __tree(__tree&& __t)
1085        _NOEXCEPT_(
1086            is_nothrow_move_constructible<__node_allocator>::value &&
1087            is_nothrow_move_constructible<value_compare>::value);
1088    __tree(__tree&& __t, const allocator_type& __a);
1089    __tree& operator=(__tree&& __t)
1090        _NOEXCEPT_(
1091            __node_traits::propagate_on_container_move_assignment::value &&
1092            is_nothrow_move_assignable<value_compare>::value &&
1093            is_nothrow_move_assignable<__node_allocator>::value);
1094#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1095
1096    ~__tree();
1097
1098    _LIBCPP_INLINE_VISIBILITY
1099          iterator begin()  _NOEXCEPT {return       iterator(__begin_node());}
1100    _LIBCPP_INLINE_VISIBILITY
1101    const_iterator begin() const _NOEXCEPT {return const_iterator(__begin_node());}
1102    _LIBCPP_INLINE_VISIBILITY
1103          iterator end() _NOEXCEPT {return       iterator(__end_node());}
1104    _LIBCPP_INLINE_VISIBILITY
1105    const_iterator end() const _NOEXCEPT {return const_iterator(__end_node());}
1106
1107    _LIBCPP_INLINE_VISIBILITY
1108    size_type max_size() const _NOEXCEPT
1109        {return __node_traits::max_size(__node_alloc());}
1110
1111    void clear() _NOEXCEPT;
1112
1113    void swap(__tree& __t)
1114#if _LIBCPP_STD_VER <= 11
1115        _NOEXCEPT_(
1116            __is_nothrow_swappable<value_compare>::value
1117            && (!__node_traits::propagate_on_container_swap::value ||
1118                 __is_nothrow_swappable<__node_allocator>::value)
1119            );
1120#else
1121        _NOEXCEPT_(__is_nothrow_swappable<value_compare>::value);
1122#endif
1123
1124#ifndef _LIBCPP_CXX03_LANG
1125    template <class _Key, class ..._Args>
1126    pair<iterator, bool>
1127    __emplace_unique_key_args(_Key const&, _Args&&... __args);
1128    template <class _Key, class ..._Args>
1129    iterator
1130    __emplace_hint_unique_key_args(const_iterator, _Key const&, _Args&&...);
1131
1132    template <class... _Args>
1133    pair<iterator, bool> __emplace_unique_impl(_Args&&... __args);
1134
1135    template <class... _Args>
1136    iterator __emplace_hint_unique_impl(const_iterator __p, _Args&&... __args);
1137
1138    template <class... _Args>
1139    iterator __emplace_multi(_Args&&... __args);
1140
1141    template <class... _Args>
1142    iterator __emplace_hint_multi(const_iterator __p, _Args&&... __args);
1143
1144    template <class _Pp>
1145    _LIBCPP_INLINE_VISIBILITY
1146    pair<iterator, bool> __emplace_unique(_Pp&& __x) {
1147        return __emplace_unique_extract_key(_VSTD::forward<_Pp>(__x),
1148                                            __can_extract_key<_Pp, key_type>());
1149    }
1150
1151    template <class _First, class _Second>
1152    _LIBCPP_INLINE_VISIBILITY
1153    typename enable_if<
1154        __can_extract_map_key<_First, key_type, __container_value_type>::value,
1155        pair<iterator, bool>
1156    >::type __emplace_unique(_First&& __f, _Second&& __s) {
1157        return __emplace_unique_key_args(__f, _VSTD::forward<_First>(__f),
1158                                              _VSTD::forward<_Second>(__s));
1159    }
1160
1161    template <class... _Args>
1162    _LIBCPP_INLINE_VISIBILITY
1163    pair<iterator, bool> __emplace_unique(_Args&&... __args) {
1164        return __emplace_unique_impl(_VSTD::forward<_Args>(__args)...);
1165    }
1166
1167    template <class _Pp>
1168    _LIBCPP_INLINE_VISIBILITY
1169    pair<iterator, bool>
1170    __emplace_unique_extract_key(_Pp&& __x, __extract_key_fail_tag) {
1171      return __emplace_unique_impl(_VSTD::forward<_Pp>(__x));
1172    }
1173
1174    template <class _Pp>
1175    _LIBCPP_INLINE_VISIBILITY
1176    pair<iterator, bool>
1177    __emplace_unique_extract_key(_Pp&& __x, __extract_key_self_tag) {
1178      return __emplace_unique_key_args(__x, _VSTD::forward<_Pp>(__x));
1179    }
1180
1181    template <class _Pp>
1182    _LIBCPP_INLINE_VISIBILITY
1183    pair<iterator, bool>
1184    __emplace_unique_extract_key(_Pp&& __x, __extract_key_first_tag) {
1185      return __emplace_unique_key_args(__x.first, _VSTD::forward<_Pp>(__x));
1186    }
1187
1188    template <class _Pp>
1189    _LIBCPP_INLINE_VISIBILITY
1190    iterator __emplace_hint_unique(const_iterator __p, _Pp&& __x) {
1191        return __emplace_hint_unique_extract_key(__p, _VSTD::forward<_Pp>(__x),
1192                                            __can_extract_key<_Pp, key_type>());
1193    }
1194
1195    template <class _First, class _Second>
1196    _LIBCPP_INLINE_VISIBILITY
1197    typename enable_if<
1198        __can_extract_map_key<_First, key_type, __container_value_type>::value,
1199        iterator
1200    >::type __emplace_hint_unique(const_iterator __p, _First&& __f, _Second&& __s) {
1201        return __emplace_hint_unique_key_args(__p, __f,
1202                                              _VSTD::forward<_First>(__f),
1203                                              _VSTD::forward<_Second>(__s));
1204    }
1205
1206    template <class... _Args>
1207    _LIBCPP_INLINE_VISIBILITY
1208    iterator __emplace_hint_unique(const_iterator __p, _Args&&... __args) {
1209        return __emplace_hint_unique_impl(__p, _VSTD::forward<_Args>(__args)...);
1210    }
1211
1212    template <class _Pp>
1213    _LIBCPP_INLINE_VISIBILITY
1214    iterator
1215    __emplace_hint_unique_extract_key(const_iterator __p, _Pp&& __x, __extract_key_fail_tag) {
1216      return __emplace_hint_unique_impl(__p, _VSTD::forward<_Pp>(__x));
1217    }
1218
1219    template <class _Pp>
1220    _LIBCPP_INLINE_VISIBILITY
1221    iterator
1222    __emplace_hint_unique_extract_key(const_iterator __p, _Pp&& __x, __extract_key_self_tag) {
1223      return __emplace_hint_unique_key_args(__p, __x, _VSTD::forward<_Pp>(__x));
1224    }
1225
1226    template <class _Pp>
1227    _LIBCPP_INLINE_VISIBILITY
1228    iterator
1229    __emplace_hint_unique_extract_key(const_iterator __p, _Pp&& __x, __extract_key_first_tag) {
1230      return __emplace_hint_unique_key_args(__p, __x.first, _VSTD::forward<_Pp>(__x));
1231    }
1232
1233#else
1234    template <class _Key, class _Args>
1235    _LIBCPP_INLINE_VISIBILITY
1236    pair<iterator, bool> __emplace_unique_key_args(_Key const&, _Args& __args);
1237    template <class _Key, class _Args>
1238    _LIBCPP_INLINE_VISIBILITY
1239    iterator __emplace_hint_unique_key_args(const_iterator, _Key const&, _Args&);
1240#endif
1241
1242    _LIBCPP_INLINE_VISIBILITY
1243    pair<iterator, bool> __insert_unique(const __container_value_type& __v) {
1244        return __emplace_unique_key_args(_NodeTypes::__get_key(__v), __v);
1245    }
1246
1247    _LIBCPP_INLINE_VISIBILITY
1248    iterator __insert_unique(const_iterator __p, const __container_value_type& __v) {
1249        return __emplace_hint_unique_key_args(__p, _NodeTypes::__get_key(__v), __v);
1250    }
1251
1252#ifdef _LIBCPP_CXX03_LANG
1253    _LIBCPP_INLINE_VISIBILITY
1254    iterator __insert_multi(const __container_value_type& __v);
1255    _LIBCPP_INLINE_VISIBILITY
1256    iterator __insert_multi(const_iterator __p, const __container_value_type& __v);
1257#else
1258    _LIBCPP_INLINE_VISIBILITY
1259    pair<iterator, bool> __insert_unique(__container_value_type&& __v) {
1260        return __emplace_unique_key_args(_NodeTypes::__get_key(__v), _VSTD::move(__v));
1261    }
1262
1263    _LIBCPP_INLINE_VISIBILITY
1264    iterator __insert_unique(const_iterator __p, __container_value_type&& __v) {
1265        return __emplace_hint_unique_key_args(__p, _NodeTypes::__get_key(__v), _VSTD::move(__v));
1266    }
1267
1268    template <class _Vp, class = typename enable_if<
1269            !is_same<typename __unconstref<_Vp>::type,
1270                     __container_value_type
1271            >::value
1272        >::type>
1273    _LIBCPP_INLINE_VISIBILITY
1274    pair<iterator, bool> __insert_unique(_Vp&& __v) {
1275        return __emplace_unique(_VSTD::forward<_Vp>(__v));
1276    }
1277
1278    template <class _Vp, class = typename enable_if<
1279            !is_same<typename __unconstref<_Vp>::type,
1280                     __container_value_type
1281            >::value
1282        >::type>
1283    _LIBCPP_INLINE_VISIBILITY
1284    iterator __insert_unique(const_iterator __p, _Vp&& __v) {
1285        return __emplace_hint_unique(__p, _VSTD::forward<_Vp>(__v));
1286    }
1287
1288    _LIBCPP_INLINE_VISIBILITY
1289    iterator __insert_multi(__container_value_type&& __v) {
1290        return __emplace_multi(_VSTD::move(__v));
1291    }
1292
1293    _LIBCPP_INLINE_VISIBILITY
1294    iterator __insert_multi(const_iterator __p, __container_value_type&& __v) {
1295        return __emplace_hint_multi(__p, _VSTD::move(__v));
1296    }
1297
1298    template <class _Vp>
1299    _LIBCPP_INLINE_VISIBILITY
1300    iterator __insert_multi(_Vp&& __v) {
1301        return __emplace_multi(_VSTD::forward<_Vp>(__v));
1302    }
1303
1304    template <class _Vp>
1305    _LIBCPP_INLINE_VISIBILITY
1306    iterator __insert_multi(const_iterator __p, _Vp&& __v) {
1307        return __emplace_hint_multi(__p, _VSTD::forward<_Vp>(__v));
1308    }
1309
1310#endif // !_LIBCPP_CXX03_LANG
1311
1312    pair<iterator, bool> __node_insert_unique(__node_pointer __nd);
1313    iterator             __node_insert_unique(const_iterator __p,
1314                                              __node_pointer __nd);
1315
1316    iterator __node_insert_multi(__node_pointer __nd);
1317    iterator __node_insert_multi(const_iterator __p, __node_pointer __nd);
1318
1319    iterator erase(const_iterator __p);
1320    iterator erase(const_iterator __f, const_iterator __l);
1321    template <class _Key>
1322        size_type __erase_unique(const _Key& __k);
1323    template <class _Key>
1324        size_type __erase_multi(const _Key& __k);
1325
1326    void __insert_node_at(__parent_pointer     __parent,
1327                          __node_base_pointer& __child,
1328                          __node_base_pointer __new_node);
1329
1330    template <class _Key>
1331        iterator find(const _Key& __v);
1332    template <class _Key>
1333        const_iterator find(const _Key& __v) const;
1334
1335    template <class _Key>
1336        size_type __count_unique(const _Key& __k) const;
1337    template <class _Key>
1338        size_type __count_multi(const _Key& __k) const;
1339
1340    template <class _Key>
1341        _LIBCPP_INLINE_VISIBILITY
1342        iterator lower_bound(const _Key& __v)
1343            {return __lower_bound(__v, __root(), __end_node());}
1344    template <class _Key>
1345        iterator __lower_bound(const _Key& __v,
1346                               __node_pointer __root,
1347                               __iter_pointer __result);
1348    template <class _Key>
1349        _LIBCPP_INLINE_VISIBILITY
1350        const_iterator lower_bound(const _Key& __v) const
1351            {return __lower_bound(__v, __root(), __end_node());}
1352    template <class _Key>
1353        const_iterator __lower_bound(const _Key& __v,
1354                                     __node_pointer __root,
1355                                     __iter_pointer __result) const;
1356    template <class _Key>
1357        _LIBCPP_INLINE_VISIBILITY
1358        iterator upper_bound(const _Key& __v)
1359            {return __upper_bound(__v, __root(), __end_node());}
1360    template <class _Key>
1361        iterator __upper_bound(const _Key& __v,
1362                               __node_pointer __root,
1363                               __iter_pointer __result);
1364    template <class _Key>
1365        _LIBCPP_INLINE_VISIBILITY
1366        const_iterator upper_bound(const _Key& __v) const
1367            {return __upper_bound(__v, __root(), __end_node());}
1368    template <class _Key>
1369        const_iterator __upper_bound(const _Key& __v,
1370                                     __node_pointer __root,
1371                                     __iter_pointer __result) const;
1372    template <class _Key>
1373        pair<iterator, iterator>
1374        __equal_range_unique(const _Key& __k);
1375    template <class _Key>
1376        pair<const_iterator, const_iterator>
1377        __equal_range_unique(const _Key& __k) const;
1378
1379    template <class _Key>
1380        pair<iterator, iterator>
1381        __equal_range_multi(const _Key& __k);
1382    template <class _Key>
1383        pair<const_iterator, const_iterator>
1384        __equal_range_multi(const _Key& __k) const;
1385
1386    typedef __tree_node_destructor<__node_allocator> _Dp;
1387    typedef unique_ptr<__node, _Dp> __node_holder;
1388
1389    __node_holder remove(const_iterator __p) _NOEXCEPT;
1390private:
1391    __node_base_pointer&
1392        __find_leaf_low(__parent_pointer& __parent, const key_type& __v);
1393    __node_base_pointer&
1394        __find_leaf_high(__parent_pointer& __parent, const key_type& __v);
1395    __node_base_pointer&
1396        __find_leaf(const_iterator __hint,
1397                    __parent_pointer& __parent, const key_type& __v);
1398    template <class _Key>
1399    __node_base_pointer&
1400        __find_equal(__parent_pointer& __parent, const _Key& __v);
1401    template <class _Key>
1402    __node_base_pointer&
1403        __find_equal(const_iterator __hint, __parent_pointer& __parent,
1404                     __node_base_pointer& __dummy,
1405                     const _Key& __v);
1406
1407#ifndef _LIBCPP_CXX03_LANG
1408    template <class ..._Args>
1409    __node_holder __construct_node(_Args&& ...__args);
1410#else
1411    __node_holder __construct_node(const __container_value_type& __v);
1412#endif
1413
1414    void destroy(__node_pointer __nd) _NOEXCEPT;
1415
1416    _LIBCPP_INLINE_VISIBILITY
1417    void __copy_assign_alloc(const __tree& __t)
1418        {__copy_assign_alloc(__t, integral_constant<bool,
1419             __node_traits::propagate_on_container_copy_assignment::value>());}
1420
1421    _LIBCPP_INLINE_VISIBILITY
1422    void __copy_assign_alloc(const __tree& __t, true_type)
1423        {
1424        if (__node_alloc() != __t.__node_alloc())
1425        	clear();
1426        __node_alloc() = __t.__node_alloc();
1427        }
1428    _LIBCPP_INLINE_VISIBILITY
1429    void __copy_assign_alloc(const __tree& __t, false_type) {}
1430
1431    void __move_assign(__tree& __t, false_type);
1432    void __move_assign(__tree& __t, true_type)
1433        _NOEXCEPT_(is_nothrow_move_assignable<value_compare>::value &&
1434                   is_nothrow_move_assignable<__node_allocator>::value);
1435
1436    _LIBCPP_INLINE_VISIBILITY
1437    void __move_assign_alloc(__tree& __t)
1438        _NOEXCEPT_(
1439            !__node_traits::propagate_on_container_move_assignment::value ||
1440            is_nothrow_move_assignable<__node_allocator>::value)
1441        {__move_assign_alloc(__t, integral_constant<bool,
1442             __node_traits::propagate_on_container_move_assignment::value>());}
1443
1444    _LIBCPP_INLINE_VISIBILITY
1445    void __move_assign_alloc(__tree& __t, true_type)
1446        _NOEXCEPT_(is_nothrow_move_assignable<__node_allocator>::value)
1447        {__node_alloc() = _VSTD::move(__t.__node_alloc());}
1448    _LIBCPP_INLINE_VISIBILITY
1449    void __move_assign_alloc(__tree& __t, false_type) _NOEXCEPT {}
1450
1451    __node_pointer __detach();
1452    static __node_pointer __detach(__node_pointer);
1453
1454    template <class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY map;
1455    template <class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY multimap;
1456};
1457
1458template <class _Tp, class _Compare, class _Allocator>
1459__tree<_Tp, _Compare, _Allocator>::__tree(const value_compare& __comp)
1460        _NOEXCEPT_(
1461            is_nothrow_default_constructible<__node_allocator>::value &&
1462            is_nothrow_copy_constructible<value_compare>::value)
1463    : __pair3_(0, __comp)
1464{
1465    __begin_node() = __end_node();
1466}
1467
1468template <class _Tp, class _Compare, class _Allocator>
1469__tree<_Tp, _Compare, _Allocator>::__tree(const allocator_type& __a)
1470    : __begin_node_(__iter_pointer()),
1471      __pair1_(__node_allocator(__a)),
1472      __pair3_(0)
1473{
1474    __begin_node() = __end_node();
1475}
1476
1477template <class _Tp, class _Compare, class _Allocator>
1478__tree<_Tp, _Compare, _Allocator>::__tree(const value_compare& __comp,
1479                                           const allocator_type& __a)
1480    : __begin_node_(__iter_pointer()),
1481      __pair1_(__node_allocator(__a)),
1482      __pair3_(0, __comp)
1483{
1484    __begin_node() = __end_node();
1485}
1486
1487// Precondition:  size() != 0
1488template <class _Tp, class _Compare, class _Allocator>
1489typename __tree<_Tp, _Compare, _Allocator>::__node_pointer
1490__tree<_Tp, _Compare, _Allocator>::__detach()
1491{
1492    __node_pointer __cache = static_cast<__node_pointer>(__begin_node());
1493    __begin_node() = __end_node();
1494    __end_node()->__left_->__parent_ = nullptr;
1495    __end_node()->__left_ = nullptr;
1496    size() = 0;
1497    // __cache->__left_ == nullptr
1498    if (__cache->__right_ != nullptr)
1499        __cache = static_cast<__node_pointer>(__cache->__right_);
1500    // __cache->__left_ == nullptr
1501    // __cache->__right_ == nullptr
1502    return __cache;
1503}
1504
1505// Precondition:  __cache != nullptr
1506//    __cache->left_ == nullptr
1507//    __cache->right_ == nullptr
1508//    This is no longer a red-black tree
1509template <class _Tp, class _Compare, class _Allocator>
1510typename __tree<_Tp, _Compare, _Allocator>::__node_pointer
1511__tree<_Tp, _Compare, _Allocator>::__detach(__node_pointer __cache)
1512{
1513    if (__cache->__parent_ == nullptr)
1514        return nullptr;
1515    if (__tree_is_left_child(static_cast<__node_base_pointer>(__cache)))
1516    {
1517        __cache->__parent_->__left_ = nullptr;
1518        __cache = static_cast<__node_pointer>(__cache->__parent_);
1519        if (__cache->__right_ == nullptr)
1520            return __cache;
1521        return static_cast<__node_pointer>(__tree_leaf(__cache->__right_));
1522    }
1523    // __cache is right child
1524    __cache->__parent_unsafe()->__right_ = nullptr;
1525    __cache = static_cast<__node_pointer>(__cache->__parent_);
1526    if (__cache->__left_ == nullptr)
1527        return __cache;
1528    return static_cast<__node_pointer>(__tree_leaf(__cache->__left_));
1529}
1530
1531template <class _Tp, class _Compare, class _Allocator>
1532__tree<_Tp, _Compare, _Allocator>&
1533__tree<_Tp, _Compare, _Allocator>::operator=(const __tree& __t)
1534{
1535    if (this != &__t)
1536    {
1537        value_comp() = __t.value_comp();
1538        __copy_assign_alloc(__t);
1539        __assign_multi(__t.begin(), __t.end());
1540    }
1541    return *this;
1542}
1543
1544template <class _Tp, class _Compare, class _Allocator>
1545template <class _InputIterator>
1546void
1547__tree<_Tp, _Compare, _Allocator>::__assign_unique(_InputIterator __first, _InputIterator __last)
1548{
1549    typedef iterator_traits<_InputIterator> _ITraits;
1550    typedef typename _ITraits::value_type _ItValueType;
1551    static_assert((is_same<_ItValueType, __container_value_type>::value),
1552                  "__assign_unique may only be called with the containers value type");
1553
1554    if (size() != 0)
1555    {
1556        __node_pointer __cache = __detach();
1557#ifndef _LIBCPP_NO_EXCEPTIONS
1558        try
1559        {
1560#endif  // _LIBCPP_NO_EXCEPTIONS
1561            for (; __cache != nullptr && __first != __last; ++__first)
1562            {
1563                __cache->__value_ = *__first;
1564                __node_pointer __next = __detach(__cache);
1565                __node_insert_unique(__cache);
1566                __cache = __next;
1567            }
1568#ifndef _LIBCPP_NO_EXCEPTIONS
1569        }
1570        catch (...)
1571        {
1572            while (__cache->__parent_ != nullptr)
1573                __cache = static_cast<__node_pointer>(__cache->__parent_);
1574            destroy(__cache);
1575            throw;
1576        }
1577#endif  // _LIBCPP_NO_EXCEPTIONS
1578        if (__cache != nullptr)
1579        {
1580            while (__cache->__parent_ != nullptr)
1581                __cache = static_cast<__node_pointer>(__cache->__parent_);
1582            destroy(__cache);
1583        }
1584    }
1585    for (; __first != __last; ++__first)
1586        __insert_unique(*__first);
1587}
1588
1589template <class _Tp, class _Compare, class _Allocator>
1590template <class _InputIterator>
1591void
1592__tree<_Tp, _Compare, _Allocator>::__assign_multi(_InputIterator __first, _InputIterator __last)
1593{
1594    typedef iterator_traits<_InputIterator> _ITraits;
1595    typedef typename _ITraits::value_type _ItValueType;
1596    static_assert((is_same<_ItValueType, __container_value_type>::value ||
1597                  is_same<_ItValueType, __node_value_type>::value),
1598                  "__assign_multi may only be called with the containers value type"
1599                  " or the nodes value type");
1600    if (size() != 0)
1601    {
1602        __node_pointer __cache = __detach();
1603#ifndef _LIBCPP_NO_EXCEPTIONS
1604        try
1605        {
1606#endif  // _LIBCPP_NO_EXCEPTIONS
1607            for (; __cache != nullptr && __first != __last; ++__first)
1608            {
1609                __cache->__value_ = *__first;
1610                __node_pointer __next = __detach(__cache);
1611                __node_insert_multi(__cache);
1612                __cache = __next;
1613            }
1614#ifndef _LIBCPP_NO_EXCEPTIONS
1615        }
1616        catch (...)
1617        {
1618            while (__cache->__parent_ != nullptr)
1619                __cache = static_cast<__node_pointer>(__cache->__parent_);
1620            destroy(__cache);
1621            throw;
1622        }
1623#endif  // _LIBCPP_NO_EXCEPTIONS
1624        if (__cache != nullptr)
1625        {
1626            while (__cache->__parent_ != nullptr)
1627                __cache = static_cast<__node_pointer>(__cache->__parent_);
1628            destroy(__cache);
1629        }
1630    }
1631    for (; __first != __last; ++__first)
1632        __insert_multi(_NodeTypes::__get_value(*__first));
1633}
1634
1635template <class _Tp, class _Compare, class _Allocator>
1636__tree<_Tp, _Compare, _Allocator>::__tree(const __tree& __t)
1637    : __begin_node_(__iter_pointer()),
1638      __pair1_(__node_traits::select_on_container_copy_construction(__t.__node_alloc())),
1639      __pair3_(0, __t.value_comp())
1640{
1641    __begin_node() = __end_node();
1642}
1643
1644#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1645
1646template <class _Tp, class _Compare, class _Allocator>
1647__tree<_Tp, _Compare, _Allocator>::__tree(__tree&& __t)
1648    _NOEXCEPT_(
1649        is_nothrow_move_constructible<__node_allocator>::value &&
1650        is_nothrow_move_constructible<value_compare>::value)
1651    : __begin_node_(_VSTD::move(__t.__begin_node_)),
1652      __pair1_(_VSTD::move(__t.__pair1_)),
1653      __pair3_(_VSTD::move(__t.__pair3_))
1654{
1655    if (size() == 0)
1656        __begin_node() = __end_node();
1657    else
1658    {
1659        __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
1660        __t.__begin_node() = __t.__end_node();
1661        __t.__end_node()->__left_ = nullptr;
1662        __t.size() = 0;
1663    }
1664}
1665
1666template <class _Tp, class _Compare, class _Allocator>
1667__tree<_Tp, _Compare, _Allocator>::__tree(__tree&& __t, const allocator_type& __a)
1668    : __pair1_(__node_allocator(__a)),
1669      __pair3_(0, _VSTD::move(__t.value_comp()))
1670{
1671    if (__a == __t.__alloc())
1672    {
1673        if (__t.size() == 0)
1674            __begin_node() = __end_node();
1675        else
1676        {
1677            __begin_node() = __t.__begin_node();
1678            __end_node()->__left_ = __t.__end_node()->__left_;
1679            __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
1680            size() = __t.size();
1681            __t.__begin_node() = __t.__end_node();
1682            __t.__end_node()->__left_ = nullptr;
1683            __t.size() = 0;
1684        }
1685    }
1686    else
1687    {
1688        __begin_node() = __end_node();
1689    }
1690}
1691
1692template <class _Tp, class _Compare, class _Allocator>
1693void
1694__tree<_Tp, _Compare, _Allocator>::__move_assign(__tree& __t, true_type)
1695    _NOEXCEPT_(is_nothrow_move_assignable<value_compare>::value &&
1696               is_nothrow_move_assignable<__node_allocator>::value)
1697{
1698    destroy(static_cast<__node_pointer>(__end_node()->__left_));
1699    __begin_node_ = __t.__begin_node_;
1700    __pair1_.first() = __t.__pair1_.first();
1701    __move_assign_alloc(__t);
1702    __pair3_ = _VSTD::move(__t.__pair3_);
1703    if (size() == 0)
1704        __begin_node() = __end_node();
1705    else
1706    {
1707        __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
1708        __t.__begin_node() = __t.__end_node();
1709        __t.__end_node()->__left_ = nullptr;
1710        __t.size() = 0;
1711    }
1712}
1713
1714template <class _Tp, class _Compare, class _Allocator>
1715void
1716__tree<_Tp, _Compare, _Allocator>::__move_assign(__tree& __t, false_type)
1717{
1718    if (__node_alloc() == __t.__node_alloc())
1719        __move_assign(__t, true_type());
1720    else
1721    {
1722        value_comp() = _VSTD::move(__t.value_comp());
1723        const_iterator __e = end();
1724        if (size() != 0)
1725        {
1726            __node_pointer __cache = __detach();
1727#ifndef _LIBCPP_NO_EXCEPTIONS
1728            try
1729            {
1730#endif  // _LIBCPP_NO_EXCEPTIONS
1731                while (__cache != nullptr && __t.size() != 0)
1732                {
1733                    __cache->__value_ = _VSTD::move(__t.remove(__t.begin())->__value_);
1734                    __node_pointer __next = __detach(__cache);
1735                    __node_insert_multi(__cache);
1736                    __cache = __next;
1737                }
1738#ifndef _LIBCPP_NO_EXCEPTIONS
1739            }
1740            catch (...)
1741            {
1742                while (__cache->__parent_ != nullptr)
1743                    __cache = static_cast<__node_pointer>(__cache->__parent_);
1744                destroy(__cache);
1745                throw;
1746            }
1747#endif  // _LIBCPP_NO_EXCEPTIONS
1748            if (__cache != nullptr)
1749            {
1750                while (__cache->__parent_ != nullptr)
1751                    __cache = static_cast<__node_pointer>(__cache->__parent_);
1752                destroy(__cache);
1753            }
1754        }
1755        while (__t.size() != 0)
1756            __insert_multi(__e, _NodeTypes::__move(__t.remove(__t.begin())->__value_));
1757    }
1758}
1759
1760template <class _Tp, class _Compare, class _Allocator>
1761__tree<_Tp, _Compare, _Allocator>&
1762__tree<_Tp, _Compare, _Allocator>::operator=(__tree&& __t)
1763    _NOEXCEPT_(
1764        __node_traits::propagate_on_container_move_assignment::value &&
1765        is_nothrow_move_assignable<value_compare>::value &&
1766        is_nothrow_move_assignable<__node_allocator>::value)
1767
1768{
1769    __move_assign(__t, integral_constant<bool,
1770                  __node_traits::propagate_on_container_move_assignment::value>());
1771    return *this;
1772}
1773
1774#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1775
1776template <class _Tp, class _Compare, class _Allocator>
1777__tree<_Tp, _Compare, _Allocator>::~__tree()
1778{
1779    static_assert((is_copy_constructible<value_compare>::value),
1780                 "Comparator must be copy-constructible.");
1781    destroy(__root());
1782}
1783
1784template <class _Tp, class _Compare, class _Allocator>
1785void
1786__tree<_Tp, _Compare, _Allocator>::destroy(__node_pointer __nd) _NOEXCEPT
1787{
1788    if (__nd != nullptr)
1789    {
1790        destroy(static_cast<__node_pointer>(__nd->__left_));
1791        destroy(static_cast<__node_pointer>(__nd->__right_));
1792        __node_allocator& __na = __node_alloc();
1793        __node_traits::destroy(__na, _NodeTypes::__get_ptr(__nd->__value_));
1794        __node_traits::deallocate(__na, __nd, 1);
1795    }
1796}
1797
1798template <class _Tp, class _Compare, class _Allocator>
1799void
1800__tree<_Tp, _Compare, _Allocator>::swap(__tree& __t)
1801#if _LIBCPP_STD_VER <= 11
1802        _NOEXCEPT_(
1803            __is_nothrow_swappable<value_compare>::value
1804            && (!__node_traits::propagate_on_container_swap::value ||
1805                 __is_nothrow_swappable<__node_allocator>::value)
1806            )
1807#else
1808        _NOEXCEPT_(__is_nothrow_swappable<value_compare>::value)
1809#endif
1810{
1811    using _VSTD::swap;
1812    swap(__begin_node_, __t.__begin_node_);
1813    swap(__pair1_.first(), __t.__pair1_.first());
1814    __swap_allocator(__node_alloc(), __t.__node_alloc());
1815    __pair3_.swap(__t.__pair3_);
1816    if (size() == 0)
1817        __begin_node() = __end_node();
1818    else
1819        __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
1820    if (__t.size() == 0)
1821        __t.__begin_node() = __t.__end_node();
1822    else
1823        __t.__end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__t.__end_node());
1824}
1825
1826template <class _Tp, class _Compare, class _Allocator>
1827void
1828__tree<_Tp, _Compare, _Allocator>::clear() _NOEXCEPT
1829{
1830    destroy(__root());
1831    size() = 0;
1832    __begin_node() = __end_node();
1833    __end_node()->__left_ = nullptr;
1834}
1835
1836// Find lower_bound place to insert
1837// Set __parent to parent of null leaf
1838// Return reference to null leaf
1839template <class _Tp, class _Compare, class _Allocator>
1840typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
1841__tree<_Tp, _Compare, _Allocator>::__find_leaf_low(__parent_pointer& __parent,
1842                                                   const key_type& __v)
1843{
1844    __node_pointer __nd = __root();
1845    if (__nd != nullptr)
1846    {
1847        while (true)
1848        {
1849            if (value_comp()(__nd->__value_, __v))
1850            {
1851                if (__nd->__right_ != nullptr)
1852                    __nd = static_cast<__node_pointer>(__nd->__right_);
1853                else
1854                {
1855                    __parent = static_cast<__parent_pointer>(__nd);
1856                    return __nd->__right_;
1857                }
1858            }
1859            else
1860            {
1861                if (__nd->__left_ != nullptr)
1862                    __nd = static_cast<__node_pointer>(__nd->__left_);
1863                else
1864                {
1865                    __parent = static_cast<__parent_pointer>(__nd);
1866                    return __parent->__left_;
1867                }
1868            }
1869        }
1870    }
1871    __parent = static_cast<__parent_pointer>(__end_node());
1872    return __parent->__left_;
1873}
1874
1875// Find upper_bound place to insert
1876// Set __parent to parent of null leaf
1877// Return reference to null leaf
1878template <class _Tp, class _Compare, class _Allocator>
1879typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
1880__tree<_Tp, _Compare, _Allocator>::__find_leaf_high(__parent_pointer& __parent,
1881                                                    const key_type& __v)
1882{
1883    __node_pointer __nd = __root();
1884    if (__nd != nullptr)
1885    {
1886        while (true)
1887        {
1888            if (value_comp()(__v, __nd->__value_))
1889            {
1890                if (__nd->__left_ != nullptr)
1891                    __nd = static_cast<__node_pointer>(__nd->__left_);
1892                else
1893                {
1894                    __parent = static_cast<__parent_pointer>(__nd);
1895                    return __parent->__left_;
1896                }
1897            }
1898            else
1899            {
1900                if (__nd->__right_ != nullptr)
1901                    __nd = static_cast<__node_pointer>(__nd->__right_);
1902                else
1903                {
1904                    __parent = static_cast<__parent_pointer>(__nd);
1905                    return __nd->__right_;
1906                }
1907            }
1908        }
1909    }
1910    __parent = static_cast<__parent_pointer>(__end_node());
1911    return __parent->__left_;
1912}
1913
1914// Find leaf place to insert closest to __hint
1915// First check prior to __hint.
1916// Next check after __hint.
1917// Next do O(log N) search.
1918// Set __parent to parent of null leaf
1919// Return reference to null leaf
1920template <class _Tp, class _Compare, class _Allocator>
1921typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
1922__tree<_Tp, _Compare, _Allocator>::__find_leaf(const_iterator __hint,
1923                                               __parent_pointer& __parent,
1924                                               const key_type& __v)
1925{
1926    if (__hint == end() || !value_comp()(*__hint, __v))  // check before
1927    {
1928        // __v <= *__hint
1929        const_iterator __prior = __hint;
1930        if (__prior == begin() || !value_comp()(__v, *--__prior))
1931        {
1932            // *prev(__hint) <= __v <= *__hint
1933            if (__hint.__ptr_->__left_ == nullptr)
1934            {
1935                __parent = static_cast<__parent_pointer>(__hint.__ptr_);
1936                return __parent->__left_;
1937            }
1938            else
1939            {
1940                __parent = static_cast<__parent_pointer>(__prior.__ptr_);
1941                return static_cast<__node_base_pointer>(__prior.__ptr_)->__right_;
1942            }
1943        }
1944        // __v < *prev(__hint)
1945        return __find_leaf_high(__parent, __v);
1946    }
1947    // else __v > *__hint
1948    return __find_leaf_low(__parent, __v);
1949}
1950
1951// Find place to insert if __v doesn't exist
1952// Set __parent to parent of null leaf
1953// Return reference to null leaf
1954// If __v exists, set parent to node of __v and return reference to node of __v
1955template <class _Tp, class _Compare, class _Allocator>
1956template <class _Key>
1957typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
1958__tree<_Tp, _Compare, _Allocator>::__find_equal(__parent_pointer& __parent,
1959                                                const _Key& __v)
1960{
1961    __node_pointer __nd = __root();
1962    __node_base_pointer* __nd_ptr = __root_ptr();
1963    if (__nd != nullptr)
1964    {
1965        while (true)
1966        {
1967            if (value_comp()(__v, __nd->__value_))
1968            {
1969                if (__nd->__left_ != nullptr) {
1970                    __nd_ptr = _VSTD::addressof(__nd->__left_);
1971                    __nd = static_cast<__node_pointer>(__nd->__left_);
1972                } else {
1973                    __parent = static_cast<__parent_pointer>(__nd);
1974                    return __parent->__left_;
1975                }
1976            }
1977            else if (value_comp()(__nd->__value_, __v))
1978            {
1979                if (__nd->__right_ != nullptr) {
1980                    __nd_ptr = _VSTD::addressof(__nd->__right_);
1981                    __nd = static_cast<__node_pointer>(__nd->__right_);
1982                } else {
1983                    __parent = static_cast<__parent_pointer>(__nd);
1984                    return __nd->__right_;
1985                }
1986            }
1987            else
1988            {
1989                __parent = static_cast<__parent_pointer>(__nd);
1990                return *__nd_ptr;
1991            }
1992        }
1993    }
1994    __parent = static_cast<__parent_pointer>(__end_node());
1995    return __parent->__left_;
1996}
1997
1998// Find place to insert if __v doesn't exist
1999// First check prior to __hint.
2000// Next check after __hint.
2001// Next do O(log N) search.
2002// Set __parent to parent of null leaf
2003// Return reference to null leaf
2004// If __v exists, set parent to node of __v and return reference to node of __v
2005template <class _Tp, class _Compare, class _Allocator>
2006template <class _Key>
2007typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
2008__tree<_Tp, _Compare, _Allocator>::__find_equal(const_iterator __hint,
2009                                                __parent_pointer& __parent,
2010                                                __node_base_pointer& __dummy,
2011                                                const _Key& __v)
2012{
2013    if (__hint == end() || value_comp()(__v, *__hint))  // check before
2014    {
2015        // __v < *__hint
2016        const_iterator __prior = __hint;
2017        if (__prior == begin() || value_comp()(*--__prior, __v))
2018        {
2019            // *prev(__hint) < __v < *__hint
2020            if (__hint.__ptr_->__left_ == nullptr)
2021            {
2022                __parent = static_cast<__parent_pointer>(__hint.__ptr_);
2023                return __parent->__left_;
2024            }
2025            else
2026            {
2027                __parent = static_cast<__parent_pointer>(__prior.__ptr_);
2028                return static_cast<__node_base_pointer>(__prior.__ptr_)->__right_;
2029            }
2030        }
2031        // __v <= *prev(__hint)
2032        return __find_equal(__parent, __v);
2033    }
2034    else if (value_comp()(*__hint, __v))  // check after
2035    {
2036        // *__hint < __v
2037        const_iterator __next = _VSTD::next(__hint);
2038        if (__next == end() || value_comp()(__v, *__next))
2039        {
2040            // *__hint < __v < *_VSTD::next(__hint)
2041            if (__hint.__get_np()->__right_ == nullptr)
2042            {
2043                __parent = static_cast<__parent_pointer>(__hint.__ptr_);
2044                return static_cast<__node_base_pointer>(__hint.__ptr_)->__right_;
2045            }
2046            else
2047            {
2048                __parent = static_cast<__parent_pointer>(__next.__ptr_);
2049                return __parent->__left_;
2050            }
2051        }
2052        // *next(__hint) <= __v
2053        return __find_equal(__parent, __v);
2054    }
2055    // else __v == *__hint
2056    __parent = static_cast<__parent_pointer>(__hint.__ptr_);
2057    __dummy = static_cast<__node_base_pointer>(__hint.__ptr_);
2058    return __dummy;
2059}
2060
2061template <class _Tp, class _Compare, class _Allocator>
2062void
2063__tree<_Tp, _Compare, _Allocator>::__insert_node_at(__parent_pointer     __parent,
2064                                                    __node_base_pointer& __child,
2065                                                    __node_base_pointer  __new_node)
2066{
2067    __new_node->__left_   = nullptr;
2068    __new_node->__right_  = nullptr;
2069    __new_node->__parent_ = __parent;
2070    // __new_node->__is_black_ is initialized in __tree_balance_after_insert
2071    __child = __new_node;
2072    if (__begin_node()->__left_ != nullptr)
2073        __begin_node() = static_cast<__iter_pointer>(__begin_node()->__left_);
2074    __tree_balance_after_insert(__end_node()->__left_, __child);
2075    ++size();
2076}
2077
2078#ifndef _LIBCPP_CXX03_LANG
2079template <class _Tp, class _Compare, class _Allocator>
2080template <class _Key, class... _Args>
2081pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
2082__tree<_Tp, _Compare, _Allocator>::__emplace_unique_key_args(_Key const& __k, _Args&&... __args)
2083#else
2084template <class _Tp, class _Compare, class _Allocator>
2085template <class _Key, class _Args>
2086pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
2087__tree<_Tp, _Compare, _Allocator>::__emplace_unique_key_args(_Key const& __k, _Args& __args)
2088#endif
2089{
2090    __parent_pointer __parent;
2091    __node_base_pointer& __child = __find_equal(__parent, __k);
2092    __node_pointer __r = static_cast<__node_pointer>(__child);
2093    bool __inserted = false;
2094    if (__child == nullptr)
2095    {
2096#ifndef _LIBCPP_CXX03_LANG
2097        __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2098#else
2099        __node_holder __h = __construct_node(__args);
2100#endif
2101        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2102        __r = __h.release();
2103        __inserted = true;
2104    }
2105    return pair<iterator, bool>(iterator(__r), __inserted);
2106}
2107
2108
2109#ifndef _LIBCPP_CXX03_LANG
2110template <class _Tp, class _Compare, class _Allocator>
2111template <class _Key, class... _Args>
2112typename __tree<_Tp, _Compare, _Allocator>::iterator
2113__tree<_Tp, _Compare, _Allocator>::__emplace_hint_unique_key_args(
2114    const_iterator __p, _Key const& __k, _Args&&... __args)
2115#else
2116template <class _Tp, class _Compare, class _Allocator>
2117template <class _Key, class _Args>
2118typename __tree<_Tp, _Compare, _Allocator>::iterator
2119__tree<_Tp, _Compare, _Allocator>::__emplace_hint_unique_key_args(
2120    const_iterator __p, _Key const& __k, _Args& __args)
2121#endif
2122{
2123    __parent_pointer __parent;
2124    __node_base_pointer __dummy;
2125    __node_base_pointer& __child = __find_equal(__p, __parent, __dummy, __k);
2126    __node_pointer __r = static_cast<__node_pointer>(__child);
2127    if (__child == nullptr)
2128    {
2129#ifndef _LIBCPP_CXX03_LANG
2130        __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2131#else
2132        __node_holder __h = __construct_node(__args);
2133#endif
2134        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2135        __r = __h.release();
2136    }
2137    return iterator(__r);
2138}
2139
2140
2141#ifndef _LIBCPP_CXX03_LANG
2142
2143template <class _Tp, class _Compare, class _Allocator>
2144template <class ..._Args>
2145typename __tree<_Tp, _Compare, _Allocator>::__node_holder
2146__tree<_Tp, _Compare, _Allocator>::__construct_node(_Args&& ...__args)
2147{
2148    static_assert(!__is_tree_value_type<_Args...>::value,
2149                  "Cannot construct from __value_type");
2150    __node_allocator& __na = __node_alloc();
2151    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
2152    __node_traits::construct(__na, _NodeTypes::__get_ptr(__h->__value_), _VSTD::forward<_Args>(__args)...);
2153    __h.get_deleter().__value_constructed = true;
2154    return __h;
2155}
2156
2157
2158template <class _Tp, class _Compare, class _Allocator>
2159template <class... _Args>
2160pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
2161__tree<_Tp, _Compare, _Allocator>::__emplace_unique_impl(_Args&&... __args)
2162{
2163    __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2164    __parent_pointer __parent;
2165    __node_base_pointer& __child = __find_equal(__parent, __h->__value_);
2166    __node_pointer __r = static_cast<__node_pointer>(__child);
2167    bool __inserted = false;
2168    if (__child == nullptr)
2169    {
2170        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2171        __r = __h.release();
2172        __inserted = true;
2173    }
2174    return pair<iterator, bool>(iterator(__r), __inserted);
2175}
2176
2177template <class _Tp, class _Compare, class _Allocator>
2178template <class... _Args>
2179typename __tree<_Tp, _Compare, _Allocator>::iterator
2180__tree<_Tp, _Compare, _Allocator>::__emplace_hint_unique_impl(const_iterator __p, _Args&&... __args)
2181{
2182    __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2183    __parent_pointer __parent;
2184    __node_base_pointer __dummy;
2185    __node_base_pointer& __child = __find_equal(__p, __parent, __dummy, __h->__value_);
2186    __node_pointer __r = static_cast<__node_pointer>(__child);
2187    if (__child == nullptr)
2188    {
2189        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2190        __r = __h.release();
2191    }
2192    return iterator(__r);
2193}
2194
2195template <class _Tp, class _Compare, class _Allocator>
2196template <class... _Args>
2197typename __tree<_Tp, _Compare, _Allocator>::iterator
2198__tree<_Tp, _Compare, _Allocator>::__emplace_multi(_Args&&... __args)
2199{
2200    __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2201    __parent_pointer __parent;
2202    __node_base_pointer& __child = __find_leaf_high(__parent, _NodeTypes::__get_key(__h->__value_));
2203    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2204    return iterator(static_cast<__node_pointer>(__h.release()));
2205}
2206
2207template <class _Tp, class _Compare, class _Allocator>
2208template <class... _Args>
2209typename __tree<_Tp, _Compare, _Allocator>::iterator
2210__tree<_Tp, _Compare, _Allocator>::__emplace_hint_multi(const_iterator __p,
2211                                                        _Args&&... __args)
2212{
2213    __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2214    __parent_pointer __parent;
2215    __node_base_pointer& __child = __find_leaf(__p, __parent, _NodeTypes::__get_key(__h->__value_));
2216    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2217    return iterator(static_cast<__node_pointer>(__h.release()));
2218}
2219
2220
2221#else  // _LIBCPP_CXX03_LANG
2222
2223template <class _Tp, class _Compare, class _Allocator>
2224typename __tree<_Tp, _Compare, _Allocator>::__node_holder
2225__tree<_Tp, _Compare, _Allocator>::__construct_node(const __container_value_type& __v)
2226{
2227    __node_allocator& __na = __node_alloc();
2228    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
2229    __node_traits::construct(__na, _NodeTypes::__get_ptr(__h->__value_), __v);
2230    __h.get_deleter().__value_constructed = true;
2231    return _LIBCPP_EXPLICIT_MOVE(__h);  // explicitly moved for C++03
2232}
2233
2234#endif  // _LIBCPP_CXX03_LANG
2235
2236#ifdef _LIBCPP_CXX03_LANG
2237template <class _Tp, class _Compare, class _Allocator>
2238typename __tree<_Tp, _Compare, _Allocator>::iterator
2239__tree<_Tp, _Compare, _Allocator>::__insert_multi(const __container_value_type& __v)
2240{
2241    __parent_pointer __parent;
2242    __node_base_pointer& __child = __find_leaf_high(__parent, _NodeTypes::__get_key(__v));
2243    __node_holder __h = __construct_node(__v);
2244    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2245    return iterator(__h.release());
2246}
2247
2248template <class _Tp, class _Compare, class _Allocator>
2249typename __tree<_Tp, _Compare, _Allocator>::iterator
2250__tree<_Tp, _Compare, _Allocator>::__insert_multi(const_iterator __p, const __container_value_type& __v)
2251{
2252    __parent_pointer __parent;
2253    __node_base_pointer& __child = __find_leaf(__p, __parent, _NodeTypes::__get_key(__v));
2254    __node_holder __h = __construct_node(__v);
2255    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2256    return iterator(__h.release());
2257}
2258#endif
2259
2260template <class _Tp, class _Compare, class _Allocator>
2261pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
2262__tree<_Tp, _Compare, _Allocator>::__node_insert_unique(__node_pointer __nd)
2263{
2264    __parent_pointer __parent;
2265    __node_base_pointer& __child = __find_equal(__parent, __nd->__value_);
2266    __node_pointer __r = static_cast<__node_pointer>(__child);
2267    bool __inserted = false;
2268    if (__child == nullptr)
2269    {
2270        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
2271        __r = __nd;
2272        __inserted = true;
2273    }
2274    return pair<iterator, bool>(iterator(__r), __inserted);
2275}
2276
2277template <class _Tp, class _Compare, class _Allocator>
2278typename __tree<_Tp, _Compare, _Allocator>::iterator
2279__tree<_Tp, _Compare, _Allocator>::__node_insert_unique(const_iterator __p,
2280                                                        __node_pointer __nd)
2281{
2282    __parent_pointer __parent;
2283    __node_base_pointer __dummy;
2284    __node_base_pointer& __child = __find_equal(__p, __parent, __nd->__value_);
2285    __node_pointer __r = static_cast<__node_pointer>(__child);
2286    if (__child == nullptr)
2287    {
2288        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
2289        __r = __nd;
2290    }
2291    return iterator(__r);
2292}
2293
2294template <class _Tp, class _Compare, class _Allocator>
2295typename __tree<_Tp, _Compare, _Allocator>::iterator
2296__tree<_Tp, _Compare, _Allocator>::__node_insert_multi(__node_pointer __nd)
2297{
2298    __parent_pointer __parent;
2299    __node_base_pointer& __child = __find_leaf_high(__parent, _NodeTypes::__get_key(__nd->__value_));
2300    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
2301    return iterator(__nd);
2302}
2303
2304template <class _Tp, class _Compare, class _Allocator>
2305typename __tree<_Tp, _Compare, _Allocator>::iterator
2306__tree<_Tp, _Compare, _Allocator>::__node_insert_multi(const_iterator __p,
2307                                                       __node_pointer __nd)
2308{
2309    __parent_pointer __parent;
2310    __node_base_pointer& __child = __find_leaf(__p, __parent, _NodeTypes::__get_key(__nd->__value_));
2311    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
2312    return iterator(__nd);
2313}
2314
2315template <class _Tp, class _Compare, class _Allocator>
2316typename __tree<_Tp, _Compare, _Allocator>::iterator
2317__tree<_Tp, _Compare, _Allocator>::erase(const_iterator __p)
2318{
2319    __node_pointer __np = __p.__get_np();
2320    iterator __r(__p.__ptr_);
2321    ++__r;
2322    if (__begin_node() == __p.__ptr_)
2323        __begin_node() = __r.__ptr_;
2324    --size();
2325    __node_allocator& __na = __node_alloc();
2326    __tree_remove(__end_node()->__left_,
2327                  static_cast<__node_base_pointer>(__np));
2328    __node_traits::destroy(__na, _NodeTypes::__get_ptr(
2329        const_cast<__node_value_type&>(*__p)));
2330    __node_traits::deallocate(__na, __np, 1);
2331    return __r;
2332}
2333
2334template <class _Tp, class _Compare, class _Allocator>
2335typename __tree<_Tp, _Compare, _Allocator>::iterator
2336__tree<_Tp, _Compare, _Allocator>::erase(const_iterator __f, const_iterator __l)
2337{
2338    while (__f != __l)
2339        __f = erase(__f);
2340    return iterator(__l.__ptr_);
2341}
2342
2343template <class _Tp, class _Compare, class _Allocator>
2344template <class _Key>
2345typename __tree<_Tp, _Compare, _Allocator>::size_type
2346__tree<_Tp, _Compare, _Allocator>::__erase_unique(const _Key& __k)
2347{
2348    iterator __i = find(__k);
2349    if (__i == end())
2350        return 0;
2351    erase(__i);
2352    return 1;
2353}
2354
2355template <class _Tp, class _Compare, class _Allocator>
2356template <class _Key>
2357typename __tree<_Tp, _Compare, _Allocator>::size_type
2358__tree<_Tp, _Compare, _Allocator>::__erase_multi(const _Key& __k)
2359{
2360    pair<iterator, iterator> __p = __equal_range_multi(__k);
2361    size_type __r = 0;
2362    for (; __p.first != __p.second; ++__r)
2363        __p.first = erase(__p.first);
2364    return __r;
2365}
2366
2367template <class _Tp, class _Compare, class _Allocator>
2368template <class _Key>
2369typename __tree<_Tp, _Compare, _Allocator>::iterator
2370__tree<_Tp, _Compare, _Allocator>::find(const _Key& __v)
2371{
2372    iterator __p = __lower_bound(__v, __root(), __end_node());
2373    if (__p != end() && !value_comp()(__v, *__p))
2374        return __p;
2375    return end();
2376}
2377
2378template <class _Tp, class _Compare, class _Allocator>
2379template <class _Key>
2380typename __tree<_Tp, _Compare, _Allocator>::const_iterator
2381__tree<_Tp, _Compare, _Allocator>::find(const _Key& __v) const
2382{
2383    const_iterator __p = __lower_bound(__v, __root(), __end_node());
2384    if (__p != end() && !value_comp()(__v, *__p))
2385        return __p;
2386    return end();
2387}
2388
2389template <class _Tp, class _Compare, class _Allocator>
2390template <class _Key>
2391typename __tree<_Tp, _Compare, _Allocator>::size_type
2392__tree<_Tp, _Compare, _Allocator>::__count_unique(const _Key& __k) const
2393{
2394    __node_pointer __rt = __root();
2395    while (__rt != nullptr)
2396    {
2397        if (value_comp()(__k, __rt->__value_))
2398        {
2399            __rt = static_cast<__node_pointer>(__rt->__left_);
2400        }
2401        else if (value_comp()(__rt->__value_, __k))
2402            __rt = static_cast<__node_pointer>(__rt->__right_);
2403        else
2404            return 1;
2405    }
2406    return 0;
2407}
2408
2409template <class _Tp, class _Compare, class _Allocator>
2410template <class _Key>
2411typename __tree<_Tp, _Compare, _Allocator>::size_type
2412__tree<_Tp, _Compare, _Allocator>::__count_multi(const _Key& __k) const
2413{
2414    __iter_pointer __result = __end_node();
2415    __node_pointer __rt = __root();
2416    while (__rt != nullptr)
2417    {
2418        if (value_comp()(__k, __rt->__value_))
2419        {
2420            __result = static_cast<__iter_pointer>(__rt);
2421            __rt = static_cast<__node_pointer>(__rt->__left_);
2422        }
2423        else if (value_comp()(__rt->__value_, __k))
2424            __rt = static_cast<__node_pointer>(__rt->__right_);
2425        else
2426            return _VSTD::distance(
2427                __lower_bound(__k, static_cast<__node_pointer>(__rt->__left_), static_cast<__iter_pointer>(__rt)),
2428                __upper_bound(__k, static_cast<__node_pointer>(__rt->__right_), __result)
2429            );
2430    }
2431    return 0;
2432}
2433
2434template <class _Tp, class _Compare, class _Allocator>
2435template <class _Key>
2436typename __tree<_Tp, _Compare, _Allocator>::iterator
2437__tree<_Tp, _Compare, _Allocator>::__lower_bound(const _Key& __v,
2438                                                 __node_pointer __root,
2439                                                 __iter_pointer __result)
2440{
2441    while (__root != nullptr)
2442    {
2443        if (!value_comp()(__root->__value_, __v))
2444        {
2445            __result = static_cast<__iter_pointer>(__root);
2446            __root = static_cast<__node_pointer>(__root->__left_);
2447        }
2448        else
2449            __root = static_cast<__node_pointer>(__root->__right_);
2450    }
2451    return iterator(__result);
2452}
2453
2454template <class _Tp, class _Compare, class _Allocator>
2455template <class _Key>
2456typename __tree<_Tp, _Compare, _Allocator>::const_iterator
2457__tree<_Tp, _Compare, _Allocator>::__lower_bound(const _Key& __v,
2458                                                 __node_pointer __root,
2459                                                 __iter_pointer __result) const
2460{
2461    while (__root != nullptr)
2462    {
2463        if (!value_comp()(__root->__value_, __v))
2464        {
2465            __result = static_cast<__iter_pointer>(__root);
2466            __root = static_cast<__node_pointer>(__root->__left_);
2467        }
2468        else
2469            __root = static_cast<__node_pointer>(__root->__right_);
2470    }
2471    return const_iterator(__result);
2472}
2473
2474template <class _Tp, class _Compare, class _Allocator>
2475template <class _Key>
2476typename __tree<_Tp, _Compare, _Allocator>::iterator
2477__tree<_Tp, _Compare, _Allocator>::__upper_bound(const _Key& __v,
2478                                                 __node_pointer __root,
2479                                                 __iter_pointer __result)
2480{
2481    while (__root != nullptr)
2482    {
2483        if (value_comp()(__v, __root->__value_))
2484        {
2485            __result = static_cast<__iter_pointer>(__root);
2486            __root = static_cast<__node_pointer>(__root->__left_);
2487        }
2488        else
2489            __root = static_cast<__node_pointer>(__root->__right_);
2490    }
2491    return iterator(__result);
2492}
2493
2494template <class _Tp, class _Compare, class _Allocator>
2495template <class _Key>
2496typename __tree<_Tp, _Compare, _Allocator>::const_iterator
2497__tree<_Tp, _Compare, _Allocator>::__upper_bound(const _Key& __v,
2498                                                 __node_pointer __root,
2499                                                 __iter_pointer __result) const
2500{
2501    while (__root != nullptr)
2502    {
2503        if (value_comp()(__v, __root->__value_))
2504        {
2505            __result = static_cast<__iter_pointer>(__root);
2506            __root = static_cast<__node_pointer>(__root->__left_);
2507        }
2508        else
2509            __root = static_cast<__node_pointer>(__root->__right_);
2510    }
2511    return const_iterator(__result);
2512}
2513
2514template <class _Tp, class _Compare, class _Allocator>
2515template <class _Key>
2516pair<typename __tree<_Tp, _Compare, _Allocator>::iterator,
2517     typename __tree<_Tp, _Compare, _Allocator>::iterator>
2518__tree<_Tp, _Compare, _Allocator>::__equal_range_unique(const _Key& __k)
2519{
2520    typedef pair<iterator, iterator> _Pp;
2521    __iter_pointer __result = __end_node();
2522    __node_pointer __rt = __root();
2523    while (__rt != nullptr)
2524    {
2525        if (value_comp()(__k, __rt->__value_))
2526        {
2527            __result = static_cast<__iter_pointer>(__rt);
2528            __rt = static_cast<__node_pointer>(__rt->__left_);
2529        }
2530        else if (value_comp()(__rt->__value_, __k))
2531            __rt = static_cast<__node_pointer>(__rt->__right_);
2532        else
2533            return _Pp(iterator(__rt),
2534                      iterator(
2535                          __rt->__right_ != nullptr ?
2536                              static_cast<__iter_pointer>(__tree_min(__rt->__right_))
2537                            : __result));
2538    }
2539    return _Pp(iterator(__result), iterator(__result));
2540}
2541
2542template <class _Tp, class _Compare, class _Allocator>
2543template <class _Key>
2544pair<typename __tree<_Tp, _Compare, _Allocator>::const_iterator,
2545     typename __tree<_Tp, _Compare, _Allocator>::const_iterator>
2546__tree<_Tp, _Compare, _Allocator>::__equal_range_unique(const _Key& __k) const
2547{
2548    typedef pair<const_iterator, const_iterator> _Pp;
2549    __iter_pointer __result = __end_node();
2550    __node_pointer __rt = __root();
2551    while (__rt != nullptr)
2552    {
2553        if (value_comp()(__k, __rt->__value_))
2554        {
2555            __result = static_cast<__iter_pointer>(__rt);
2556            __rt = static_cast<__node_pointer>(__rt->__left_);
2557        }
2558        else if (value_comp()(__rt->__value_, __k))
2559            __rt = static_cast<__node_pointer>(__rt->__right_);
2560        else
2561            return _Pp(const_iterator(__rt),
2562                      const_iterator(
2563                          __rt->__right_ != nullptr ?
2564                              static_cast<__iter_pointer>(__tree_min(__rt->__right_))
2565                            : __result));
2566    }
2567    return _Pp(const_iterator(__result), const_iterator(__result));
2568}
2569
2570template <class _Tp, class _Compare, class _Allocator>
2571template <class _Key>
2572pair<typename __tree<_Tp, _Compare, _Allocator>::iterator,
2573     typename __tree<_Tp, _Compare, _Allocator>::iterator>
2574__tree<_Tp, _Compare, _Allocator>::__equal_range_multi(const _Key& __k)
2575{
2576    typedef pair<iterator, iterator> _Pp;
2577    __iter_pointer __result = __end_node();
2578    __node_pointer __rt = __root();
2579    while (__rt != nullptr)
2580    {
2581        if (value_comp()(__k, __rt->__value_))
2582        {
2583            __result = static_cast<__iter_pointer>(__rt);
2584            __rt = static_cast<__node_pointer>(__rt->__left_);
2585        }
2586        else if (value_comp()(__rt->__value_, __k))
2587            __rt = static_cast<__node_pointer>(__rt->__right_);
2588        else
2589            return _Pp(__lower_bound(__k, static_cast<__node_pointer>(__rt->__left_), static_cast<__iter_pointer>(__rt)),
2590                      __upper_bound(__k, static_cast<__node_pointer>(__rt->__right_), __result));
2591    }
2592    return _Pp(iterator(__result), iterator(__result));
2593}
2594
2595template <class _Tp, class _Compare, class _Allocator>
2596template <class _Key>
2597pair<typename __tree<_Tp, _Compare, _Allocator>::const_iterator,
2598     typename __tree<_Tp, _Compare, _Allocator>::const_iterator>
2599__tree<_Tp, _Compare, _Allocator>::__equal_range_multi(const _Key& __k) const
2600{
2601    typedef pair<const_iterator, const_iterator> _Pp;
2602    __iter_pointer __result = __end_node();
2603    __node_pointer __rt = __root();
2604    while (__rt != nullptr)
2605    {
2606        if (value_comp()(__k, __rt->__value_))
2607        {
2608            __result = static_cast<__iter_pointer>(__rt);
2609            __rt = static_cast<__node_pointer>(__rt->__left_);
2610        }
2611        else if (value_comp()(__rt->__value_, __k))
2612            __rt = static_cast<__node_pointer>(__rt->__right_);
2613        else
2614            return _Pp(__lower_bound(__k, static_cast<__node_pointer>(__rt->__left_), static_cast<__iter_pointer>(__rt)),
2615                      __upper_bound(__k, static_cast<__node_pointer>(__rt->__right_), __result));
2616    }
2617    return _Pp(const_iterator(__result), const_iterator(__result));
2618}
2619
2620template <class _Tp, class _Compare, class _Allocator>
2621typename __tree<_Tp, _Compare, _Allocator>::__node_holder
2622__tree<_Tp, _Compare, _Allocator>::remove(const_iterator __p) _NOEXCEPT
2623{
2624    __node_pointer __np = __p.__get_np();
2625    if (__begin_node() == __p.__ptr_)
2626    {
2627        if (__np->__right_ != nullptr)
2628            __begin_node() = static_cast<__iter_pointer>(__np->__right_);
2629        else
2630            __begin_node() = static_cast<__iter_pointer>(__np->__parent_);
2631    }
2632    --size();
2633    __tree_remove(__end_node()->__left_,
2634                  static_cast<__node_base_pointer>(__np));
2635    return __node_holder(__np, _Dp(__node_alloc(), true));
2636}
2637
2638template <class _Tp, class _Compare, class _Allocator>
2639inline _LIBCPP_INLINE_VISIBILITY
2640void
2641swap(__tree<_Tp, _Compare, _Allocator>& __x,
2642     __tree<_Tp, _Compare, _Allocator>& __y)
2643    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
2644{
2645    __x.swap(__y);
2646}
2647
2648_LIBCPP_END_NAMESPACE_STD
2649
2650#endif  // _LIBCPP___TREE
2651