xref: /freebsd/contrib/llvm-project/libcxx/include/__tree (revision b0d29bc47dba79f6f38e67eabadfb4b32ffd9390)
1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP___TREE
11#define _LIBCPP___TREE
12
13#include <__config>
14#include <iterator>
15#include <memory>
16#include <stdexcept>
17#include <algorithm>
18
19#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
20#pragma GCC system_header
21#endif
22
23_LIBCPP_PUSH_MACROS
24#include <__undef_macros>
25
26
27_LIBCPP_BEGIN_NAMESPACE_STD
28
29#if defined(__GNUC__) && !defined(__clang__) // gcc.gnu.org/PR37804
30template <class, class, class, class> class _LIBCPP_TEMPLATE_VIS map;
31template <class, class, class, class> class _LIBCPP_TEMPLATE_VIS multimap;
32template <class, class, class> class _LIBCPP_TEMPLATE_VIS set;
33template <class, class, class> class _LIBCPP_TEMPLATE_VIS multiset;
34#endif
35
36template <class _Tp, class _Compare, class _Allocator> class __tree;
37template <class _Tp, class _NodePtr, class _DiffType>
38    class _LIBCPP_TEMPLATE_VIS __tree_iterator;
39template <class _Tp, class _ConstNodePtr, class _DiffType>
40    class _LIBCPP_TEMPLATE_VIS __tree_const_iterator;
41
42template <class _Pointer> class __tree_end_node;
43template <class _VoidPtr> class __tree_node_base;
44template <class _Tp, class _VoidPtr> class __tree_node;
45
46template <class _Key, class _Value>
47struct __value_type;
48
49template <class _Allocator> class __map_node_destructor;
50template <class _TreeIterator> class _LIBCPP_TEMPLATE_VIS __map_iterator;
51template <class _TreeIterator> class _LIBCPP_TEMPLATE_VIS __map_const_iterator;
52
53/*
54
55_NodePtr algorithms
56
57The algorithms taking _NodePtr are red black tree algorithms.  Those
58algorithms taking a parameter named __root should assume that __root
59points to a proper red black tree (unless otherwise specified).
60
61Each algorithm herein assumes that __root->__parent_ points to a non-null
62structure which has a member __left_ which points back to __root.  No other
63member is read or written to at __root->__parent_.
64
65__root->__parent_ will be referred to below (in comments only) as end_node.
66end_node->__left_ is an externably accessible lvalue for __root, and can be
67changed by node insertion and removal (without explicit reference to end_node).
68
69All nodes (with the exception of end_node), even the node referred to as
70__root, have a non-null __parent_ field.
71
72*/
73
74// Returns:  true if __x is a left child of its parent, else false
75// Precondition:  __x != nullptr.
76template <class _NodePtr>
77inline _LIBCPP_INLINE_VISIBILITY
78bool
79__tree_is_left_child(_NodePtr __x) _NOEXCEPT
80{
81    return __x == __x->__parent_->__left_;
82}
83
84// Determines if the subtree rooted at __x is a proper red black subtree.  If
85//    __x is a proper subtree, returns the black height (null counts as 1).  If
86//    __x is an improper subtree, returns 0.
87template <class _NodePtr>
88unsigned
89__tree_sub_invariant(_NodePtr __x)
90{
91    if (__x == nullptr)
92        return 1;
93    // parent consistency checked by caller
94    // check __x->__left_ consistency
95    if (__x->__left_ != nullptr && __x->__left_->__parent_ != __x)
96        return 0;
97    // check __x->__right_ consistency
98    if (__x->__right_ != nullptr && __x->__right_->__parent_ != __x)
99        return 0;
100    // check __x->__left_ != __x->__right_ unless both are nullptr
101    if (__x->__left_ == __x->__right_ && __x->__left_ != nullptr)
102        return 0;
103    // If this is red, neither child can be red
104    if (!__x->__is_black_)
105    {
106        if (__x->__left_ && !__x->__left_->__is_black_)
107            return 0;
108        if (__x->__right_ && !__x->__right_->__is_black_)
109            return 0;
110    }
111    unsigned __h = __tree_sub_invariant(__x->__left_);
112    if (__h == 0)
113        return 0;  // invalid left subtree
114    if (__h != __tree_sub_invariant(__x->__right_))
115        return 0;  // invalid or different height right subtree
116    return __h + __x->__is_black_;  // return black height of this node
117}
118
119// Determines if the red black tree rooted at __root is a proper red black tree.
120//    __root == nullptr is a proper tree.  Returns true is __root is a proper
121//    red black tree, else returns false.
122template <class _NodePtr>
123bool
124__tree_invariant(_NodePtr __root)
125{
126    if (__root == nullptr)
127        return true;
128    // check __x->__parent_ consistency
129    if (__root->__parent_ == nullptr)
130        return false;
131    if (!__tree_is_left_child(__root))
132        return false;
133    // root must be black
134    if (!__root->__is_black_)
135        return false;
136    // do normal node checks
137    return __tree_sub_invariant(__root) != 0;
138}
139
140// Returns:  pointer to the left-most node under __x.
141// Precondition:  __x != nullptr.
142template <class _NodePtr>
143inline _LIBCPP_INLINE_VISIBILITY
144_NodePtr
145__tree_min(_NodePtr __x) _NOEXCEPT
146{
147    while (__x->__left_ != nullptr)
148        __x = __x->__left_;
149    return __x;
150}
151
152// Returns:  pointer to the right-most node under __x.
153// Precondition:  __x != nullptr.
154template <class _NodePtr>
155inline _LIBCPP_INLINE_VISIBILITY
156_NodePtr
157__tree_max(_NodePtr __x) _NOEXCEPT
158{
159    while (__x->__right_ != nullptr)
160        __x = __x->__right_;
161    return __x;
162}
163
164// Returns:  pointer to the next in-order node after __x.
165// Precondition:  __x != nullptr.
166template <class _NodePtr>
167_NodePtr
168__tree_next(_NodePtr __x) _NOEXCEPT
169{
170    if (__x->__right_ != nullptr)
171        return __tree_min(__x->__right_);
172    while (!__tree_is_left_child(__x))
173        __x = __x->__parent_unsafe();
174    return __x->__parent_unsafe();
175}
176
177template <class _EndNodePtr, class _NodePtr>
178inline _LIBCPP_INLINE_VISIBILITY
179_EndNodePtr
180__tree_next_iter(_NodePtr __x) _NOEXCEPT
181{
182    if (__x->__right_ != nullptr)
183        return static_cast<_EndNodePtr>(__tree_min(__x->__right_));
184    while (!__tree_is_left_child(__x))
185        __x = __x->__parent_unsafe();
186    return static_cast<_EndNodePtr>(__x->__parent_);
187}
188
189// Returns:  pointer to the previous in-order node before __x.
190// Precondition:  __x != nullptr.
191// Note: __x may be the end node.
192template <class _NodePtr, class _EndNodePtr>
193inline _LIBCPP_INLINE_VISIBILITY
194_NodePtr
195__tree_prev_iter(_EndNodePtr __x) _NOEXCEPT
196{
197    if (__x->__left_ != nullptr)
198        return __tree_max(__x->__left_);
199    _NodePtr __xx = static_cast<_NodePtr>(__x);
200    while (__tree_is_left_child(__xx))
201        __xx = __xx->__parent_unsafe();
202    return __xx->__parent_unsafe();
203}
204
205// Returns:  pointer to a node which has no children
206// Precondition:  __x != nullptr.
207template <class _NodePtr>
208_NodePtr
209__tree_leaf(_NodePtr __x) _NOEXCEPT
210{
211    while (true)
212    {
213        if (__x->__left_ != nullptr)
214        {
215            __x = __x->__left_;
216            continue;
217        }
218        if (__x->__right_ != nullptr)
219        {
220            __x = __x->__right_;
221            continue;
222        }
223        break;
224    }
225    return __x;
226}
227
228// Effects:  Makes __x->__right_ the subtree root with __x as its left child
229//           while preserving in-order order.
230// Precondition:  __x->__right_ != nullptr
231template <class _NodePtr>
232void
233__tree_left_rotate(_NodePtr __x) _NOEXCEPT
234{
235    _NodePtr __y = __x->__right_;
236    __x->__right_ = __y->__left_;
237    if (__x->__right_ != nullptr)
238        __x->__right_->__set_parent(__x);
239    __y->__parent_ = __x->__parent_;
240    if (__tree_is_left_child(__x))
241        __x->__parent_->__left_ = __y;
242    else
243        __x->__parent_unsafe()->__right_ = __y;
244    __y->__left_ = __x;
245    __x->__set_parent(__y);
246}
247
248// Effects:  Makes __x->__left_ the subtree root with __x as its right child
249//           while preserving in-order order.
250// Precondition:  __x->__left_ != nullptr
251template <class _NodePtr>
252void
253__tree_right_rotate(_NodePtr __x) _NOEXCEPT
254{
255    _NodePtr __y = __x->__left_;
256    __x->__left_ = __y->__right_;
257    if (__x->__left_ != nullptr)
258        __x->__left_->__set_parent(__x);
259    __y->__parent_ = __x->__parent_;
260    if (__tree_is_left_child(__x))
261        __x->__parent_->__left_ = __y;
262    else
263        __x->__parent_unsafe()->__right_ = __y;
264    __y->__right_ = __x;
265    __x->__set_parent(__y);
266}
267
268// Effects:  Rebalances __root after attaching __x to a leaf.
269// Precondition:  __root != nulptr && __x != nullptr.
270//                __x has no children.
271//                __x == __root or == a direct or indirect child of __root.
272//                If __x were to be unlinked from __root (setting __root to
273//                  nullptr if __root == __x), __tree_invariant(__root) == true.
274// Postcondition: __tree_invariant(end_node->__left_) == true.  end_node->__left_
275//                may be different than the value passed in as __root.
276template <class _NodePtr>
277void
278__tree_balance_after_insert(_NodePtr __root, _NodePtr __x) _NOEXCEPT
279{
280    __x->__is_black_ = __x == __root;
281    while (__x != __root && !__x->__parent_unsafe()->__is_black_)
282    {
283        // __x->__parent_ != __root because __x->__parent_->__is_black == false
284        if (__tree_is_left_child(__x->__parent_unsafe()))
285        {
286            _NodePtr __y = __x->__parent_unsafe()->__parent_unsafe()->__right_;
287            if (__y != nullptr && !__y->__is_black_)
288            {
289                __x = __x->__parent_unsafe();
290                __x->__is_black_ = true;
291                __x = __x->__parent_unsafe();
292                __x->__is_black_ = __x == __root;
293                __y->__is_black_ = true;
294            }
295            else
296            {
297                if (!__tree_is_left_child(__x))
298                {
299                    __x = __x->__parent_unsafe();
300                    __tree_left_rotate(__x);
301                }
302                __x = __x->__parent_unsafe();
303                __x->__is_black_ = true;
304                __x = __x->__parent_unsafe();
305                __x->__is_black_ = false;
306                __tree_right_rotate(__x);
307                break;
308            }
309        }
310        else
311        {
312            _NodePtr __y = __x->__parent_unsafe()->__parent_->__left_;
313            if (__y != nullptr && !__y->__is_black_)
314            {
315                __x = __x->__parent_unsafe();
316                __x->__is_black_ = true;
317                __x = __x->__parent_unsafe();
318                __x->__is_black_ = __x == __root;
319                __y->__is_black_ = true;
320            }
321            else
322            {
323                if (__tree_is_left_child(__x))
324                {
325                    __x = __x->__parent_unsafe();
326                    __tree_right_rotate(__x);
327                }
328                __x = __x->__parent_unsafe();
329                __x->__is_black_ = true;
330                __x = __x->__parent_unsafe();
331                __x->__is_black_ = false;
332                __tree_left_rotate(__x);
333                break;
334            }
335        }
336    }
337}
338
339// Precondition:  __root != nullptr && __z != nullptr.
340//                __tree_invariant(__root) == true.
341//                __z == __root or == a direct or indirect child of __root.
342// Effects:  unlinks __z from the tree rooted at __root, rebalancing as needed.
343// Postcondition: __tree_invariant(end_node->__left_) == true && end_node->__left_
344//                nor any of its children refer to __z.  end_node->__left_
345//                may be different than the value passed in as __root.
346template <class _NodePtr>
347void
348__tree_remove(_NodePtr __root, _NodePtr __z) _NOEXCEPT
349{
350    // __z will be removed from the tree.  Client still needs to destruct/deallocate it
351    // __y is either __z, or if __z has two children, __tree_next(__z).
352    // __y will have at most one child.
353    // __y will be the initial hole in the tree (make the hole at a leaf)
354    _NodePtr __y = (__z->__left_ == nullptr || __z->__right_ == nullptr) ?
355                    __z : __tree_next(__z);
356    // __x is __y's possibly null single child
357    _NodePtr __x = __y->__left_ != nullptr ? __y->__left_ : __y->__right_;
358    // __w is __x's possibly null uncle (will become __x's sibling)
359    _NodePtr __w = nullptr;
360    // link __x to __y's parent, and find __w
361    if (__x != nullptr)
362        __x->__parent_ = __y->__parent_;
363    if (__tree_is_left_child(__y))
364    {
365        __y->__parent_->__left_ = __x;
366        if (__y != __root)
367            __w = __y->__parent_unsafe()->__right_;
368        else
369            __root = __x;  // __w == nullptr
370    }
371    else
372    {
373        __y->__parent_unsafe()->__right_ = __x;
374        // __y can't be root if it is a right child
375        __w = __y->__parent_->__left_;
376    }
377    bool __removed_black = __y->__is_black_;
378    // If we didn't remove __z, do so now by splicing in __y for __z,
379    //    but copy __z's color.  This does not impact __x or __w.
380    if (__y != __z)
381    {
382        // __z->__left_ != nulptr but __z->__right_ might == __x == nullptr
383        __y->__parent_ = __z->__parent_;
384        if (__tree_is_left_child(__z))
385            __y->__parent_->__left_ = __y;
386        else
387            __y->__parent_unsafe()->__right_ = __y;
388        __y->__left_ = __z->__left_;
389        __y->__left_->__set_parent(__y);
390        __y->__right_ = __z->__right_;
391        if (__y->__right_ != nullptr)
392            __y->__right_->__set_parent(__y);
393        __y->__is_black_ = __z->__is_black_;
394        if (__root == __z)
395            __root = __y;
396    }
397    // There is no need to rebalance if we removed a red, or if we removed
398    //     the last node.
399    if (__removed_black && __root != nullptr)
400    {
401        // Rebalance:
402        // __x has an implicit black color (transferred from the removed __y)
403        //    associated with it, no matter what its color is.
404        // If __x is __root (in which case it can't be null), it is supposed
405        //    to be black anyway, and if it is doubly black, then the double
406        //    can just be ignored.
407        // If __x is red (in which case it can't be null), then it can absorb
408        //    the implicit black just by setting its color to black.
409        // Since __y was black and only had one child (which __x points to), __x
410        //   is either red with no children, else null, otherwise __y would have
411        //   different black heights under left and right pointers.
412        // if (__x == __root || __x != nullptr && !__x->__is_black_)
413        if (__x != nullptr)
414            __x->__is_black_ = true;
415        else
416        {
417            //  Else __x isn't root, and is "doubly black", even though it may
418            //     be null.  __w can not be null here, else the parent would
419            //     see a black height >= 2 on the __x side and a black height
420            //     of 1 on the __w side (__w must be a non-null black or a red
421            //     with a non-null black child).
422            while (true)
423            {
424                if (!__tree_is_left_child(__w))  // if x is left child
425                {
426                    if (!__w->__is_black_)
427                    {
428                        __w->__is_black_ = true;
429                        __w->__parent_unsafe()->__is_black_ = false;
430                        __tree_left_rotate(__w->__parent_unsafe());
431                        // __x is still valid
432                        // reset __root only if necessary
433                        if (__root == __w->__left_)
434                            __root = __w;
435                        // reset sibling, and it still can't be null
436                        __w = __w->__left_->__right_;
437                    }
438                    // __w->__is_black_ is now true, __w may have null children
439                    if ((__w->__left_  == nullptr || __w->__left_->__is_black_) &&
440                        (__w->__right_ == nullptr || __w->__right_->__is_black_))
441                    {
442                        __w->__is_black_ = false;
443                        __x = __w->__parent_unsafe();
444                        // __x can no longer be null
445                        if (__x == __root || !__x->__is_black_)
446                        {
447                            __x->__is_black_ = true;
448                            break;
449                        }
450                        // reset sibling, and it still can't be null
451                        __w = __tree_is_left_child(__x) ?
452                                    __x->__parent_unsafe()->__right_ :
453                                    __x->__parent_->__left_;
454                        // continue;
455                    }
456                    else  // __w has a red child
457                    {
458                        if (__w->__right_ == nullptr || __w->__right_->__is_black_)
459                        {
460                            // __w left child is non-null and red
461                            __w->__left_->__is_black_ = true;
462                            __w->__is_black_ = false;
463                            __tree_right_rotate(__w);
464                            // __w is known not to be root, so root hasn't changed
465                            // reset sibling, and it still can't be null
466                            __w = __w->__parent_unsafe();
467                        }
468                        // __w has a right red child, left child may be null
469                        __w->__is_black_ = __w->__parent_unsafe()->__is_black_;
470                        __w->__parent_unsafe()->__is_black_ = true;
471                        __w->__right_->__is_black_ = true;
472                        __tree_left_rotate(__w->__parent_unsafe());
473                        break;
474                    }
475                }
476                else
477                {
478                    if (!__w->__is_black_)
479                    {
480                        __w->__is_black_ = true;
481                        __w->__parent_unsafe()->__is_black_ = false;
482                        __tree_right_rotate(__w->__parent_unsafe());
483                        // __x is still valid
484                        // reset __root only if necessary
485                        if (__root == __w->__right_)
486                            __root = __w;
487                        // reset sibling, and it still can't be null
488                        __w = __w->__right_->__left_;
489                    }
490                    // __w->__is_black_ is now true, __w may have null children
491                    if ((__w->__left_  == nullptr || __w->__left_->__is_black_) &&
492                        (__w->__right_ == nullptr || __w->__right_->__is_black_))
493                    {
494                        __w->__is_black_ = false;
495                        __x = __w->__parent_unsafe();
496                        // __x can no longer be null
497                        if (!__x->__is_black_ || __x == __root)
498                        {
499                            __x->__is_black_ = true;
500                            break;
501                        }
502                        // reset sibling, and it still can't be null
503                        __w = __tree_is_left_child(__x) ?
504                                    __x->__parent_unsafe()->__right_ :
505                                    __x->__parent_->__left_;
506                        // continue;
507                    }
508                    else  // __w has a red child
509                    {
510                        if (__w->__left_ == nullptr || __w->__left_->__is_black_)
511                        {
512                            // __w right child is non-null and red
513                            __w->__right_->__is_black_ = true;
514                            __w->__is_black_ = false;
515                            __tree_left_rotate(__w);
516                            // __w is known not to be root, so root hasn't changed
517                            // reset sibling, and it still can't be null
518                            __w = __w->__parent_unsafe();
519                        }
520                        // __w has a left red child, right child may be null
521                        __w->__is_black_ = __w->__parent_unsafe()->__is_black_;
522                        __w->__parent_unsafe()->__is_black_ = true;
523                        __w->__left_->__is_black_ = true;
524                        __tree_right_rotate(__w->__parent_unsafe());
525                        break;
526                    }
527                }
528            }
529        }
530    }
531}
532
533// node traits
534
535
536#ifndef _LIBCPP_CXX03_LANG
537template <class _Tp>
538struct __is_tree_value_type_imp : false_type {};
539
540template <class _Key, class _Value>
541struct __is_tree_value_type_imp<__value_type<_Key, _Value>> : true_type {};
542
543template <class ..._Args>
544struct __is_tree_value_type : false_type {};
545
546template <class _One>
547struct __is_tree_value_type<_One> : __is_tree_value_type_imp<typename __uncvref<_One>::type> {};
548#endif
549
550template <class _Tp>
551struct __tree_key_value_types {
552  typedef _Tp key_type;
553  typedef _Tp __node_value_type;
554  typedef _Tp __container_value_type;
555  static const bool __is_map = false;
556
557  _LIBCPP_INLINE_VISIBILITY
558  static key_type const& __get_key(_Tp const& __v) {
559    return __v;
560  }
561  _LIBCPP_INLINE_VISIBILITY
562  static __container_value_type const& __get_value(__node_value_type const& __v) {
563    return __v;
564  }
565  _LIBCPP_INLINE_VISIBILITY
566  static __container_value_type* __get_ptr(__node_value_type& __n) {
567    return _VSTD::addressof(__n);
568  }
569#ifndef _LIBCPP_CXX03_LANG
570  _LIBCPP_INLINE_VISIBILITY
571  static __container_value_type&& __move(__node_value_type& __v) {
572    return _VSTD::move(__v);
573  }
574#endif
575};
576
577template <class _Key, class _Tp>
578struct __tree_key_value_types<__value_type<_Key, _Tp> > {
579  typedef _Key                                         key_type;
580  typedef _Tp                                          mapped_type;
581  typedef __value_type<_Key, _Tp>                      __node_value_type;
582  typedef pair<const _Key, _Tp>                        __container_value_type;
583  typedef __container_value_type                       __map_value_type;
584  static const bool __is_map = true;
585
586  _LIBCPP_INLINE_VISIBILITY
587  static key_type const&
588  __get_key(__node_value_type const& __t) {
589    return __t.__get_value().first;
590  }
591
592  template <class _Up>
593  _LIBCPP_INLINE_VISIBILITY
594  static typename enable_if<__is_same_uncvref<_Up, __container_value_type>::value,
595      key_type const&>::type
596  __get_key(_Up& __t) {
597    return __t.first;
598  }
599
600  _LIBCPP_INLINE_VISIBILITY
601  static __container_value_type const&
602  __get_value(__node_value_type const& __t) {
603    return __t.__get_value();
604  }
605
606  template <class _Up>
607  _LIBCPP_INLINE_VISIBILITY
608  static typename enable_if<__is_same_uncvref<_Up, __container_value_type>::value,
609      __container_value_type const&>::type
610  __get_value(_Up& __t) {
611    return __t;
612  }
613
614  _LIBCPP_INLINE_VISIBILITY
615  static __container_value_type* __get_ptr(__node_value_type& __n) {
616    return _VSTD::addressof(__n.__get_value());
617  }
618
619#ifndef _LIBCPP_CXX03_LANG
620  _LIBCPP_INLINE_VISIBILITY
621  static pair<key_type&&, mapped_type&&> __move(__node_value_type& __v) {
622    return __v.__move();
623  }
624#endif
625};
626
627template <class _VoidPtr>
628struct __tree_node_base_types {
629  typedef _VoidPtr                                               __void_pointer;
630
631  typedef __tree_node_base<__void_pointer>                      __node_base_type;
632  typedef typename __rebind_pointer<_VoidPtr, __node_base_type>::type
633                                                             __node_base_pointer;
634
635  typedef __tree_end_node<__node_base_pointer>                  __end_node_type;
636  typedef typename __rebind_pointer<_VoidPtr, __end_node_type>::type
637                                                             __end_node_pointer;
638#if defined(_LIBCPP_ABI_TREE_REMOVE_NODE_POINTER_UB)
639  typedef __end_node_pointer __parent_pointer;
640#else
641  typedef typename conditional<
642      is_pointer<__end_node_pointer>::value,
643        __end_node_pointer,
644        __node_base_pointer>::type __parent_pointer;
645#endif
646
647private:
648  static_assert((is_same<typename pointer_traits<_VoidPtr>::element_type, void>::value),
649                  "_VoidPtr does not point to unqualified void type");
650};
651
652template <class _Tp, class _AllocPtr, class _KVTypes = __tree_key_value_types<_Tp>,
653         bool = _KVTypes::__is_map>
654struct __tree_map_pointer_types {};
655
656template <class _Tp, class _AllocPtr, class _KVTypes>
657struct __tree_map_pointer_types<_Tp, _AllocPtr, _KVTypes, true> {
658  typedef typename _KVTypes::__map_value_type   _Mv;
659  typedef typename __rebind_pointer<_AllocPtr, _Mv>::type
660                                                       __map_value_type_pointer;
661  typedef typename __rebind_pointer<_AllocPtr, const _Mv>::type
662                                                 __const_map_value_type_pointer;
663};
664
665template <class _NodePtr, class _NodeT = typename pointer_traits<_NodePtr>::element_type>
666struct __tree_node_types;
667
668template <class _NodePtr, class _Tp, class _VoidPtr>
669struct __tree_node_types<_NodePtr, __tree_node<_Tp, _VoidPtr> >
670    : public __tree_node_base_types<_VoidPtr>,
671             __tree_key_value_types<_Tp>,
672             __tree_map_pointer_types<_Tp, _VoidPtr>
673{
674  typedef __tree_node_base_types<_VoidPtr> __base;
675  typedef __tree_key_value_types<_Tp>      __key_base;
676  typedef __tree_map_pointer_types<_Tp, _VoidPtr> __map_pointer_base;
677public:
678
679  typedef typename pointer_traits<_NodePtr>::element_type       __node_type;
680  typedef _NodePtr                                              __node_pointer;
681
682  typedef _Tp                                                 __node_value_type;
683  typedef typename __rebind_pointer<_VoidPtr, __node_value_type>::type
684                                                      __node_value_type_pointer;
685  typedef typename __rebind_pointer<_VoidPtr, const __node_value_type>::type
686                                                __const_node_value_type_pointer;
687#if defined(_LIBCPP_ABI_TREE_REMOVE_NODE_POINTER_UB)
688  typedef typename __base::__end_node_pointer __iter_pointer;
689#else
690  typedef typename conditional<
691      is_pointer<__node_pointer>::value,
692        typename __base::__end_node_pointer,
693        __node_pointer>::type __iter_pointer;
694#endif
695private:
696    static_assert(!is_const<__node_type>::value,
697                "_NodePtr should never be a pointer to const");
698    static_assert((is_same<typename __rebind_pointer<_VoidPtr, __node_type>::type,
699                          _NodePtr>::value), "_VoidPtr does not rebind to _NodePtr.");
700};
701
702template <class _ValueTp, class _VoidPtr>
703struct __make_tree_node_types {
704  typedef typename __rebind_pointer<_VoidPtr, __tree_node<_ValueTp, _VoidPtr> >::type
705                                                                        _NodePtr;
706  typedef __tree_node_types<_NodePtr> type;
707};
708
709// node
710
711template <class _Pointer>
712class __tree_end_node
713{
714public:
715    typedef _Pointer pointer;
716    pointer __left_;
717
718    _LIBCPP_INLINE_VISIBILITY
719    __tree_end_node() _NOEXCEPT : __left_() {}
720};
721
722template <class _VoidPtr>
723class __tree_node_base
724    : public __tree_node_base_types<_VoidPtr>::__end_node_type
725{
726    typedef __tree_node_base_types<_VoidPtr> _NodeBaseTypes;
727
728public:
729    typedef typename _NodeBaseTypes::__node_base_pointer pointer;
730    typedef typename _NodeBaseTypes::__parent_pointer __parent_pointer;
731
732    pointer          __right_;
733    __parent_pointer __parent_;
734    bool __is_black_;
735
736    _LIBCPP_INLINE_VISIBILITY
737    pointer __parent_unsafe() const { return static_cast<pointer>(__parent_);}
738
739    _LIBCPP_INLINE_VISIBILITY
740    void __set_parent(pointer __p) {
741        __parent_ = static_cast<__parent_pointer>(__p);
742    }
743
744private:
745  ~__tree_node_base() _LIBCPP_EQUAL_DELETE;
746  __tree_node_base(__tree_node_base const&) _LIBCPP_EQUAL_DELETE;
747  __tree_node_base& operator=(__tree_node_base const&) _LIBCPP_EQUAL_DELETE;
748};
749
750template <class _Tp, class _VoidPtr>
751class __tree_node
752    : public __tree_node_base<_VoidPtr>
753{
754public:
755    typedef _Tp __node_value_type;
756
757    __node_value_type __value_;
758
759private:
760  ~__tree_node() _LIBCPP_EQUAL_DELETE;
761  __tree_node(__tree_node const&) _LIBCPP_EQUAL_DELETE;
762  __tree_node& operator=(__tree_node const&) _LIBCPP_EQUAL_DELETE;
763};
764
765
766template <class _Allocator>
767class __tree_node_destructor
768{
769    typedef _Allocator                                      allocator_type;
770    typedef allocator_traits<allocator_type>                __alloc_traits;
771
772public:
773    typedef typename __alloc_traits::pointer                pointer;
774private:
775    typedef __tree_node_types<pointer> _NodeTypes;
776    allocator_type& __na_;
777
778
779public:
780    bool __value_constructed;
781
782
783    __tree_node_destructor(const __tree_node_destructor &) = default;
784    __tree_node_destructor& operator=(const __tree_node_destructor&) = delete;
785
786    _LIBCPP_INLINE_VISIBILITY
787    explicit __tree_node_destructor(allocator_type& __na, bool __val = false) _NOEXCEPT
788        : __na_(__na),
789          __value_constructed(__val)
790        {}
791
792    _LIBCPP_INLINE_VISIBILITY
793    void operator()(pointer __p) _NOEXCEPT
794    {
795        if (__value_constructed)
796            __alloc_traits::destroy(__na_, _NodeTypes::__get_ptr(__p->__value_));
797        if (__p)
798            __alloc_traits::deallocate(__na_, __p, 1);
799    }
800
801    template <class> friend class __map_node_destructor;
802};
803
804#if _LIBCPP_STD_VER > 14
805template <class _NodeType, class _Alloc>
806struct __generic_container_node_destructor;
807template <class _Tp, class _VoidPtr, class _Alloc>
808struct __generic_container_node_destructor<__tree_node<_Tp, _VoidPtr>, _Alloc>
809    : __tree_node_destructor<_Alloc>
810{
811    using __tree_node_destructor<_Alloc>::__tree_node_destructor;
812};
813#endif
814
815template <class _Tp, class _NodePtr, class _DiffType>
816class _LIBCPP_TEMPLATE_VIS __tree_iterator
817{
818    typedef __tree_node_types<_NodePtr>                     _NodeTypes;
819    typedef _NodePtr                                        __node_pointer;
820    typedef typename _NodeTypes::__node_base_pointer        __node_base_pointer;
821    typedef typename _NodeTypes::__end_node_pointer         __end_node_pointer;
822    typedef typename _NodeTypes::__iter_pointer             __iter_pointer;
823    typedef pointer_traits<__node_pointer> __pointer_traits;
824
825    __iter_pointer __ptr_;
826
827public:
828    typedef bidirectional_iterator_tag                     iterator_category;
829    typedef _Tp                                            value_type;
830    typedef _DiffType                                      difference_type;
831    typedef value_type&                                    reference;
832    typedef typename _NodeTypes::__node_value_type_pointer pointer;
833
834    _LIBCPP_INLINE_VISIBILITY __tree_iterator() _NOEXCEPT
835#if _LIBCPP_STD_VER > 11
836    : __ptr_(nullptr)
837#endif
838    {}
839
840    _LIBCPP_INLINE_VISIBILITY reference operator*() const
841        {return __get_np()->__value_;}
842    _LIBCPP_INLINE_VISIBILITY pointer operator->() const
843        {return pointer_traits<pointer>::pointer_to(__get_np()->__value_);}
844
845    _LIBCPP_INLINE_VISIBILITY
846    __tree_iterator& operator++() {
847      __ptr_ = static_cast<__iter_pointer>(
848          __tree_next_iter<__end_node_pointer>(static_cast<__node_base_pointer>(__ptr_)));
849      return *this;
850    }
851    _LIBCPP_INLINE_VISIBILITY
852    __tree_iterator operator++(int)
853        {__tree_iterator __t(*this); ++(*this); return __t;}
854
855    _LIBCPP_INLINE_VISIBILITY
856    __tree_iterator& operator--() {
857      __ptr_ = static_cast<__iter_pointer>(__tree_prev_iter<__node_base_pointer>(
858          static_cast<__end_node_pointer>(__ptr_)));
859      return *this;
860    }
861    _LIBCPP_INLINE_VISIBILITY
862    __tree_iterator operator--(int)
863        {__tree_iterator __t(*this); --(*this); return __t;}
864
865    friend _LIBCPP_INLINE_VISIBILITY
866        bool operator==(const __tree_iterator& __x, const __tree_iterator& __y)
867        {return __x.__ptr_ == __y.__ptr_;}
868    friend _LIBCPP_INLINE_VISIBILITY
869        bool operator!=(const __tree_iterator& __x, const __tree_iterator& __y)
870        {return !(__x == __y);}
871
872private:
873    _LIBCPP_INLINE_VISIBILITY
874    explicit __tree_iterator(__node_pointer __p) _NOEXCEPT : __ptr_(__p) {}
875    _LIBCPP_INLINE_VISIBILITY
876    explicit __tree_iterator(__end_node_pointer __p) _NOEXCEPT : __ptr_(__p) {}
877    _LIBCPP_INLINE_VISIBILITY
878    __node_pointer __get_np() const { return static_cast<__node_pointer>(__ptr_); }
879    template <class, class, class> friend class __tree;
880    template <class, class, class> friend class _LIBCPP_TEMPLATE_VIS __tree_const_iterator;
881    template <class> friend class _LIBCPP_TEMPLATE_VIS __map_iterator;
882    template <class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS map;
883    template <class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS multimap;
884    template <class, class, class> friend class _LIBCPP_TEMPLATE_VIS set;
885    template <class, class, class> friend class _LIBCPP_TEMPLATE_VIS multiset;
886};
887
888template <class _Tp, class _NodePtr, class _DiffType>
889class _LIBCPP_TEMPLATE_VIS __tree_const_iterator
890{
891    typedef __tree_node_types<_NodePtr>                     _NodeTypes;
892    typedef typename _NodeTypes::__node_pointer             __node_pointer;
893    typedef typename _NodeTypes::__node_base_pointer        __node_base_pointer;
894    typedef typename _NodeTypes::__end_node_pointer         __end_node_pointer;
895    typedef typename _NodeTypes::__iter_pointer             __iter_pointer;
896    typedef pointer_traits<__node_pointer> __pointer_traits;
897
898    __iter_pointer __ptr_;
899
900public:
901    typedef bidirectional_iterator_tag                           iterator_category;
902    typedef _Tp                                                  value_type;
903    typedef _DiffType                                            difference_type;
904    typedef const value_type&                                    reference;
905    typedef typename _NodeTypes::__const_node_value_type_pointer pointer;
906
907    _LIBCPP_INLINE_VISIBILITY __tree_const_iterator() _NOEXCEPT
908#if _LIBCPP_STD_VER > 11
909    : __ptr_(nullptr)
910#endif
911    {}
912
913private:
914    typedef __tree_iterator<value_type, __node_pointer, difference_type>
915                                                           __non_const_iterator;
916public:
917    _LIBCPP_INLINE_VISIBILITY
918    __tree_const_iterator(__non_const_iterator __p) _NOEXCEPT
919        : __ptr_(__p.__ptr_) {}
920
921    _LIBCPP_INLINE_VISIBILITY reference operator*() const
922        {return __get_np()->__value_;}
923    _LIBCPP_INLINE_VISIBILITY pointer operator->() const
924        {return pointer_traits<pointer>::pointer_to(__get_np()->__value_);}
925
926    _LIBCPP_INLINE_VISIBILITY
927    __tree_const_iterator& operator++() {
928      __ptr_ = static_cast<__iter_pointer>(
929          __tree_next_iter<__end_node_pointer>(static_cast<__node_base_pointer>(__ptr_)));
930      return *this;
931    }
932
933    _LIBCPP_INLINE_VISIBILITY
934    __tree_const_iterator operator++(int)
935        {__tree_const_iterator __t(*this); ++(*this); return __t;}
936
937    _LIBCPP_INLINE_VISIBILITY
938    __tree_const_iterator& operator--() {
939      __ptr_ = static_cast<__iter_pointer>(__tree_prev_iter<__node_base_pointer>(
940          static_cast<__end_node_pointer>(__ptr_)));
941      return *this;
942    }
943
944    _LIBCPP_INLINE_VISIBILITY
945    __tree_const_iterator operator--(int)
946        {__tree_const_iterator __t(*this); --(*this); return __t;}
947
948    friend _LIBCPP_INLINE_VISIBILITY
949        bool operator==(const __tree_const_iterator& __x, const __tree_const_iterator& __y)
950        {return __x.__ptr_ == __y.__ptr_;}
951    friend _LIBCPP_INLINE_VISIBILITY
952        bool operator!=(const __tree_const_iterator& __x, const __tree_const_iterator& __y)
953        {return !(__x == __y);}
954
955private:
956    _LIBCPP_INLINE_VISIBILITY
957    explicit __tree_const_iterator(__node_pointer __p) _NOEXCEPT
958        : __ptr_(__p) {}
959    _LIBCPP_INLINE_VISIBILITY
960    explicit __tree_const_iterator(__end_node_pointer __p) _NOEXCEPT
961        : __ptr_(__p) {}
962    _LIBCPP_INLINE_VISIBILITY
963    __node_pointer __get_np() const { return static_cast<__node_pointer>(__ptr_); }
964
965    template <class, class, class> friend class __tree;
966    template <class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS map;
967    template <class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS multimap;
968    template <class, class, class> friend class _LIBCPP_TEMPLATE_VIS set;
969    template <class, class, class> friend class _LIBCPP_TEMPLATE_VIS multiset;
970    template <class> friend class _LIBCPP_TEMPLATE_VIS __map_const_iterator;
971
972};
973
974template<class _Tp, class _Compare>
975#ifndef _LIBCPP_CXX03_LANG
976    _LIBCPP_DIAGNOSE_WARNING(!std::__invokable<_Compare const&, _Tp const&, _Tp const&>::value,
977        "the specified comparator type does not provide a viable const call operator")
978#endif
979int __diagnose_non_const_comparator();
980
981template <class _Tp, class _Compare, class _Allocator>
982class __tree
983{
984public:
985    typedef _Tp                                      value_type;
986    typedef _Compare                                 value_compare;
987    typedef _Allocator                               allocator_type;
988
989private:
990    typedef allocator_traits<allocator_type>         __alloc_traits;
991    typedef typename __make_tree_node_types<value_type,
992        typename __alloc_traits::void_pointer>::type
993                                                    _NodeTypes;
994    typedef typename _NodeTypes::key_type           key_type;
995public:
996    typedef typename _NodeTypes::__node_value_type      __node_value_type;
997    typedef typename _NodeTypes::__container_value_type __container_value_type;
998
999    typedef typename __alloc_traits::pointer         pointer;
1000    typedef typename __alloc_traits::const_pointer   const_pointer;
1001    typedef typename __alloc_traits::size_type       size_type;
1002    typedef typename __alloc_traits::difference_type difference_type;
1003
1004public:
1005    typedef typename _NodeTypes::__void_pointer        __void_pointer;
1006
1007    typedef typename _NodeTypes::__node_type           __node;
1008    typedef typename _NodeTypes::__node_pointer        __node_pointer;
1009
1010    typedef typename _NodeTypes::__node_base_type      __node_base;
1011    typedef typename _NodeTypes::__node_base_pointer   __node_base_pointer;
1012
1013    typedef typename _NodeTypes::__end_node_type       __end_node_t;
1014    typedef typename _NodeTypes::__end_node_pointer    __end_node_ptr;
1015
1016    typedef typename _NodeTypes::__parent_pointer      __parent_pointer;
1017    typedef typename _NodeTypes::__iter_pointer        __iter_pointer;
1018
1019    typedef typename __rebind_alloc_helper<__alloc_traits, __node>::type __node_allocator;
1020    typedef allocator_traits<__node_allocator>         __node_traits;
1021
1022private:
1023    // check for sane allocator pointer rebinding semantics. Rebinding the
1024    // allocator for a new pointer type should be exactly the same as rebinding
1025    // the pointer using 'pointer_traits'.
1026    static_assert((is_same<__node_pointer, typename __node_traits::pointer>::value),
1027                  "Allocator does not rebind pointers in a sane manner.");
1028    typedef typename __rebind_alloc_helper<__node_traits, __node_base>::type
1029        __node_base_allocator;
1030    typedef allocator_traits<__node_base_allocator> __node_base_traits;
1031    static_assert((is_same<__node_base_pointer, typename __node_base_traits::pointer>::value),
1032                 "Allocator does not rebind pointers in a sane manner.");
1033
1034private:
1035    __iter_pointer                                     __begin_node_;
1036    __compressed_pair<__end_node_t, __node_allocator>  __pair1_;
1037    __compressed_pair<size_type, value_compare>        __pair3_;
1038
1039public:
1040    _LIBCPP_INLINE_VISIBILITY
1041    __iter_pointer __end_node() _NOEXCEPT
1042    {
1043        return static_cast<__iter_pointer>(
1044                pointer_traits<__end_node_ptr>::pointer_to(__pair1_.first())
1045        );
1046    }
1047    _LIBCPP_INLINE_VISIBILITY
1048    __iter_pointer __end_node() const _NOEXCEPT
1049    {
1050        return static_cast<__iter_pointer>(
1051            pointer_traits<__end_node_ptr>::pointer_to(
1052                const_cast<__end_node_t&>(__pair1_.first())
1053            )
1054        );
1055    }
1056    _LIBCPP_INLINE_VISIBILITY
1057          __node_allocator& __node_alloc() _NOEXCEPT {return __pair1_.second();}
1058private:
1059    _LIBCPP_INLINE_VISIBILITY
1060    const __node_allocator& __node_alloc() const _NOEXCEPT
1061        {return __pair1_.second();}
1062    _LIBCPP_INLINE_VISIBILITY
1063          __iter_pointer& __begin_node() _NOEXCEPT {return __begin_node_;}
1064    _LIBCPP_INLINE_VISIBILITY
1065    const __iter_pointer& __begin_node() const _NOEXCEPT {return __begin_node_;}
1066public:
1067    _LIBCPP_INLINE_VISIBILITY
1068    allocator_type __alloc() const _NOEXCEPT
1069        {return allocator_type(__node_alloc());}
1070private:
1071    _LIBCPP_INLINE_VISIBILITY
1072          size_type& size() _NOEXCEPT {return __pair3_.first();}
1073public:
1074    _LIBCPP_INLINE_VISIBILITY
1075    const size_type& size() const _NOEXCEPT {return __pair3_.first();}
1076    _LIBCPP_INLINE_VISIBILITY
1077          value_compare& value_comp() _NOEXCEPT {return __pair3_.second();}
1078    _LIBCPP_INLINE_VISIBILITY
1079    const value_compare& value_comp() const _NOEXCEPT
1080        {return __pair3_.second();}
1081public:
1082
1083    _LIBCPP_INLINE_VISIBILITY
1084    __node_pointer __root() const _NOEXCEPT
1085        {return static_cast<__node_pointer>(__end_node()->__left_);}
1086
1087    __node_base_pointer* __root_ptr() const _NOEXCEPT {
1088        return _VSTD::addressof(__end_node()->__left_);
1089    }
1090
1091    typedef __tree_iterator<value_type, __node_pointer, difference_type>             iterator;
1092    typedef __tree_const_iterator<value_type, __node_pointer, difference_type> const_iterator;
1093
1094    explicit __tree(const value_compare& __comp)
1095        _NOEXCEPT_(
1096            is_nothrow_default_constructible<__node_allocator>::value &&
1097            is_nothrow_copy_constructible<value_compare>::value);
1098    explicit __tree(const allocator_type& __a);
1099    __tree(const value_compare& __comp, const allocator_type& __a);
1100    __tree(const __tree& __t);
1101    __tree& operator=(const __tree& __t);
1102    template <class _ForwardIterator>
1103        void __assign_unique(_ForwardIterator __first, _ForwardIterator __last);
1104    template <class _InputIterator>
1105        void __assign_multi(_InputIterator __first, _InputIterator __last);
1106#ifndef _LIBCPP_CXX03_LANG
1107    __tree(__tree&& __t)
1108        _NOEXCEPT_(
1109            is_nothrow_move_constructible<__node_allocator>::value &&
1110            is_nothrow_move_constructible<value_compare>::value);
1111    __tree(__tree&& __t, const allocator_type& __a);
1112    __tree& operator=(__tree&& __t)
1113        _NOEXCEPT_(
1114            __node_traits::propagate_on_container_move_assignment::value &&
1115            is_nothrow_move_assignable<value_compare>::value &&
1116            is_nothrow_move_assignable<__node_allocator>::value);
1117#endif // _LIBCPP_CXX03_LANG
1118
1119    ~__tree();
1120
1121    _LIBCPP_INLINE_VISIBILITY
1122          iterator begin()  _NOEXCEPT {return       iterator(__begin_node());}
1123    _LIBCPP_INLINE_VISIBILITY
1124    const_iterator begin() const _NOEXCEPT {return const_iterator(__begin_node());}
1125    _LIBCPP_INLINE_VISIBILITY
1126          iterator end() _NOEXCEPT {return       iterator(__end_node());}
1127    _LIBCPP_INLINE_VISIBILITY
1128    const_iterator end() const _NOEXCEPT {return const_iterator(__end_node());}
1129
1130    _LIBCPP_INLINE_VISIBILITY
1131    size_type max_size() const _NOEXCEPT
1132        {return std::min<size_type>(
1133                __node_traits::max_size(__node_alloc()),
1134                numeric_limits<difference_type >::max());}
1135
1136    void clear() _NOEXCEPT;
1137
1138    void swap(__tree& __t)
1139#if _LIBCPP_STD_VER <= 11
1140        _NOEXCEPT_(
1141            __is_nothrow_swappable<value_compare>::value
1142            && (!__node_traits::propagate_on_container_swap::value ||
1143                 __is_nothrow_swappable<__node_allocator>::value)
1144            );
1145#else
1146        _NOEXCEPT_(__is_nothrow_swappable<value_compare>::value);
1147#endif
1148
1149#ifndef _LIBCPP_CXX03_LANG
1150    template <class _Key, class ..._Args>
1151    pair<iterator, bool>
1152    __emplace_unique_key_args(_Key const&, _Args&&... __args);
1153    template <class _Key, class ..._Args>
1154    iterator
1155    __emplace_hint_unique_key_args(const_iterator, _Key const&, _Args&&...);
1156
1157    template <class... _Args>
1158    pair<iterator, bool> __emplace_unique_impl(_Args&&... __args);
1159
1160    template <class... _Args>
1161    iterator __emplace_hint_unique_impl(const_iterator __p, _Args&&... __args);
1162
1163    template <class... _Args>
1164    iterator __emplace_multi(_Args&&... __args);
1165
1166    template <class... _Args>
1167    iterator __emplace_hint_multi(const_iterator __p, _Args&&... __args);
1168
1169    template <class _Pp>
1170    _LIBCPP_INLINE_VISIBILITY
1171    pair<iterator, bool> __emplace_unique(_Pp&& __x) {
1172        return __emplace_unique_extract_key(_VSTD::forward<_Pp>(__x),
1173                                            __can_extract_key<_Pp, key_type>());
1174    }
1175
1176    template <class _First, class _Second>
1177    _LIBCPP_INLINE_VISIBILITY
1178    typename enable_if<
1179        __can_extract_map_key<_First, key_type, __container_value_type>::value,
1180        pair<iterator, bool>
1181    >::type __emplace_unique(_First&& __f, _Second&& __s) {
1182        return __emplace_unique_key_args(__f, _VSTD::forward<_First>(__f),
1183                                              _VSTD::forward<_Second>(__s));
1184    }
1185
1186    template <class... _Args>
1187    _LIBCPP_INLINE_VISIBILITY
1188    pair<iterator, bool> __emplace_unique(_Args&&... __args) {
1189        return __emplace_unique_impl(_VSTD::forward<_Args>(__args)...);
1190    }
1191
1192    template <class _Pp>
1193    _LIBCPP_INLINE_VISIBILITY
1194    pair<iterator, bool>
1195    __emplace_unique_extract_key(_Pp&& __x, __extract_key_fail_tag) {
1196      return __emplace_unique_impl(_VSTD::forward<_Pp>(__x));
1197    }
1198
1199    template <class _Pp>
1200    _LIBCPP_INLINE_VISIBILITY
1201    pair<iterator, bool>
1202    __emplace_unique_extract_key(_Pp&& __x, __extract_key_self_tag) {
1203      return __emplace_unique_key_args(__x, _VSTD::forward<_Pp>(__x));
1204    }
1205
1206    template <class _Pp>
1207    _LIBCPP_INLINE_VISIBILITY
1208    pair<iterator, bool>
1209    __emplace_unique_extract_key(_Pp&& __x, __extract_key_first_tag) {
1210      return __emplace_unique_key_args(__x.first, _VSTD::forward<_Pp>(__x));
1211    }
1212
1213    template <class _Pp>
1214    _LIBCPP_INLINE_VISIBILITY
1215    iterator __emplace_hint_unique(const_iterator __p, _Pp&& __x) {
1216        return __emplace_hint_unique_extract_key(__p, _VSTD::forward<_Pp>(__x),
1217                                            __can_extract_key<_Pp, key_type>());
1218    }
1219
1220    template <class _First, class _Second>
1221    _LIBCPP_INLINE_VISIBILITY
1222    typename enable_if<
1223        __can_extract_map_key<_First, key_type, __container_value_type>::value,
1224        iterator
1225    >::type __emplace_hint_unique(const_iterator __p, _First&& __f, _Second&& __s) {
1226        return __emplace_hint_unique_key_args(__p, __f,
1227                                              _VSTD::forward<_First>(__f),
1228                                              _VSTD::forward<_Second>(__s));
1229    }
1230
1231    template <class... _Args>
1232    _LIBCPP_INLINE_VISIBILITY
1233    iterator __emplace_hint_unique(const_iterator __p, _Args&&... __args) {
1234        return __emplace_hint_unique_impl(__p, _VSTD::forward<_Args>(__args)...);
1235    }
1236
1237    template <class _Pp>
1238    _LIBCPP_INLINE_VISIBILITY
1239    iterator
1240    __emplace_hint_unique_extract_key(const_iterator __p, _Pp&& __x, __extract_key_fail_tag) {
1241      return __emplace_hint_unique_impl(__p, _VSTD::forward<_Pp>(__x));
1242    }
1243
1244    template <class _Pp>
1245    _LIBCPP_INLINE_VISIBILITY
1246    iterator
1247    __emplace_hint_unique_extract_key(const_iterator __p, _Pp&& __x, __extract_key_self_tag) {
1248      return __emplace_hint_unique_key_args(__p, __x, _VSTD::forward<_Pp>(__x));
1249    }
1250
1251    template <class _Pp>
1252    _LIBCPP_INLINE_VISIBILITY
1253    iterator
1254    __emplace_hint_unique_extract_key(const_iterator __p, _Pp&& __x, __extract_key_first_tag) {
1255      return __emplace_hint_unique_key_args(__p, __x.first, _VSTD::forward<_Pp>(__x));
1256    }
1257
1258#else
1259    template <class _Key, class _Args>
1260    _LIBCPP_INLINE_VISIBILITY
1261    pair<iterator, bool> __emplace_unique_key_args(_Key const&, _Args& __args);
1262    template <class _Key, class _Args>
1263    _LIBCPP_INLINE_VISIBILITY
1264    iterator __emplace_hint_unique_key_args(const_iterator, _Key const&, _Args&);
1265#endif
1266
1267    _LIBCPP_INLINE_VISIBILITY
1268    pair<iterator, bool> __insert_unique(const __container_value_type& __v) {
1269        return __emplace_unique_key_args(_NodeTypes::__get_key(__v), __v);
1270    }
1271
1272    _LIBCPP_INLINE_VISIBILITY
1273    iterator __insert_unique(const_iterator __p, const __container_value_type& __v) {
1274        return __emplace_hint_unique_key_args(__p, _NodeTypes::__get_key(__v), __v);
1275    }
1276
1277#ifdef _LIBCPP_CXX03_LANG
1278    _LIBCPP_INLINE_VISIBILITY
1279    iterator __insert_multi(const __container_value_type& __v);
1280    _LIBCPP_INLINE_VISIBILITY
1281    iterator __insert_multi(const_iterator __p, const __container_value_type& __v);
1282#else
1283    _LIBCPP_INLINE_VISIBILITY
1284    pair<iterator, bool> __insert_unique(__container_value_type&& __v) {
1285        return __emplace_unique_key_args(_NodeTypes::__get_key(__v), _VSTD::move(__v));
1286    }
1287
1288    _LIBCPP_INLINE_VISIBILITY
1289    iterator __insert_unique(const_iterator __p, __container_value_type&& __v) {
1290        return __emplace_hint_unique_key_args(__p, _NodeTypes::__get_key(__v), _VSTD::move(__v));
1291    }
1292
1293    template <class _Vp, class = typename enable_if<
1294            !is_same<typename __unconstref<_Vp>::type,
1295                     __container_value_type
1296            >::value
1297        >::type>
1298    _LIBCPP_INLINE_VISIBILITY
1299    pair<iterator, bool> __insert_unique(_Vp&& __v) {
1300        return __emplace_unique(_VSTD::forward<_Vp>(__v));
1301    }
1302
1303    template <class _Vp, class = typename enable_if<
1304            !is_same<typename __unconstref<_Vp>::type,
1305                     __container_value_type
1306            >::value
1307        >::type>
1308    _LIBCPP_INLINE_VISIBILITY
1309    iterator __insert_unique(const_iterator __p, _Vp&& __v) {
1310        return __emplace_hint_unique(__p, _VSTD::forward<_Vp>(__v));
1311    }
1312
1313    _LIBCPP_INLINE_VISIBILITY
1314    iterator __insert_multi(__container_value_type&& __v) {
1315        return __emplace_multi(_VSTD::move(__v));
1316    }
1317
1318    _LIBCPP_INLINE_VISIBILITY
1319    iterator __insert_multi(const_iterator __p, __container_value_type&& __v) {
1320        return __emplace_hint_multi(__p, _VSTD::move(__v));
1321    }
1322
1323    template <class _Vp>
1324    _LIBCPP_INLINE_VISIBILITY
1325    iterator __insert_multi(_Vp&& __v) {
1326        return __emplace_multi(_VSTD::forward<_Vp>(__v));
1327    }
1328
1329    template <class _Vp>
1330    _LIBCPP_INLINE_VISIBILITY
1331    iterator __insert_multi(const_iterator __p, _Vp&& __v) {
1332        return __emplace_hint_multi(__p, _VSTD::forward<_Vp>(__v));
1333    }
1334
1335#endif // !_LIBCPP_CXX03_LANG
1336
1337    _LIBCPP_INLINE_VISIBILITY
1338    pair<iterator, bool> __node_assign_unique(const __container_value_type& __v, __node_pointer __dest);
1339
1340    _LIBCPP_INLINE_VISIBILITY
1341    iterator __node_insert_multi(__node_pointer __nd);
1342    _LIBCPP_INLINE_VISIBILITY
1343    iterator __node_insert_multi(const_iterator __p, __node_pointer __nd);
1344
1345
1346    _LIBCPP_INLINE_VISIBILITY iterator
1347    __remove_node_pointer(__node_pointer) _NOEXCEPT;
1348
1349#if _LIBCPP_STD_VER > 14
1350    template <class _NodeHandle, class _InsertReturnType>
1351    _LIBCPP_INLINE_VISIBILITY
1352    _InsertReturnType __node_handle_insert_unique(_NodeHandle&&);
1353    template <class _NodeHandle>
1354    _LIBCPP_INLINE_VISIBILITY
1355    iterator __node_handle_insert_unique(const_iterator, _NodeHandle&&);
1356    template <class _Tree>
1357    _LIBCPP_INLINE_VISIBILITY
1358    void __node_handle_merge_unique(_Tree& __source);
1359
1360    template <class _NodeHandle>
1361    _LIBCPP_INLINE_VISIBILITY
1362    iterator __node_handle_insert_multi(_NodeHandle&&);
1363    template <class _NodeHandle>
1364    _LIBCPP_INLINE_VISIBILITY
1365    iterator __node_handle_insert_multi(const_iterator, _NodeHandle&&);
1366    template <class _Tree>
1367    _LIBCPP_INLINE_VISIBILITY
1368    void __node_handle_merge_multi(_Tree& __source);
1369
1370
1371    template <class _NodeHandle>
1372    _LIBCPP_INLINE_VISIBILITY
1373    _NodeHandle __node_handle_extract(key_type const&);
1374    template <class _NodeHandle>
1375    _LIBCPP_INLINE_VISIBILITY
1376    _NodeHandle __node_handle_extract(const_iterator);
1377#endif
1378
1379    iterator erase(const_iterator __p);
1380    iterator erase(const_iterator __f, const_iterator __l);
1381    template <class _Key>
1382        size_type __erase_unique(const _Key& __k);
1383    template <class _Key>
1384        size_type __erase_multi(const _Key& __k);
1385
1386    void __insert_node_at(__parent_pointer     __parent,
1387                          __node_base_pointer& __child,
1388                          __node_base_pointer __new_node) _NOEXCEPT;
1389
1390    template <class _Key>
1391        iterator find(const _Key& __v);
1392    template <class _Key>
1393        const_iterator find(const _Key& __v) const;
1394
1395    template <class _Key>
1396        size_type __count_unique(const _Key& __k) const;
1397    template <class _Key>
1398        size_type __count_multi(const _Key& __k) const;
1399
1400    template <class _Key>
1401        _LIBCPP_INLINE_VISIBILITY
1402        iterator lower_bound(const _Key& __v)
1403            {return __lower_bound(__v, __root(), __end_node());}
1404    template <class _Key>
1405        iterator __lower_bound(const _Key& __v,
1406                               __node_pointer __root,
1407                               __iter_pointer __result);
1408    template <class _Key>
1409        _LIBCPP_INLINE_VISIBILITY
1410        const_iterator lower_bound(const _Key& __v) const
1411            {return __lower_bound(__v, __root(), __end_node());}
1412    template <class _Key>
1413        const_iterator __lower_bound(const _Key& __v,
1414                                     __node_pointer __root,
1415                                     __iter_pointer __result) const;
1416    template <class _Key>
1417        _LIBCPP_INLINE_VISIBILITY
1418        iterator upper_bound(const _Key& __v)
1419            {return __upper_bound(__v, __root(), __end_node());}
1420    template <class _Key>
1421        iterator __upper_bound(const _Key& __v,
1422                               __node_pointer __root,
1423                               __iter_pointer __result);
1424    template <class _Key>
1425        _LIBCPP_INLINE_VISIBILITY
1426        const_iterator upper_bound(const _Key& __v) const
1427            {return __upper_bound(__v, __root(), __end_node());}
1428    template <class _Key>
1429        const_iterator __upper_bound(const _Key& __v,
1430                                     __node_pointer __root,
1431                                     __iter_pointer __result) const;
1432    template <class _Key>
1433        pair<iterator, iterator>
1434        __equal_range_unique(const _Key& __k);
1435    template <class _Key>
1436        pair<const_iterator, const_iterator>
1437        __equal_range_unique(const _Key& __k) const;
1438
1439    template <class _Key>
1440        pair<iterator, iterator>
1441        __equal_range_multi(const _Key& __k);
1442    template <class _Key>
1443        pair<const_iterator, const_iterator>
1444        __equal_range_multi(const _Key& __k) const;
1445
1446    typedef __tree_node_destructor<__node_allocator> _Dp;
1447    typedef unique_ptr<__node, _Dp> __node_holder;
1448
1449    __node_holder remove(const_iterator __p) _NOEXCEPT;
1450private:
1451    __node_base_pointer&
1452        __find_leaf_low(__parent_pointer& __parent, const key_type& __v);
1453    __node_base_pointer&
1454        __find_leaf_high(__parent_pointer& __parent, const key_type& __v);
1455    __node_base_pointer&
1456        __find_leaf(const_iterator __hint,
1457                    __parent_pointer& __parent, const key_type& __v);
1458    // FIXME: Make this function const qualified. Unfortunetly doing so
1459    // breaks existing code which uses non-const callable comparators.
1460    template <class _Key>
1461    __node_base_pointer&
1462        __find_equal(__parent_pointer& __parent, const _Key& __v);
1463    template <class _Key>
1464    _LIBCPP_INLINE_VISIBILITY __node_base_pointer&
1465    __find_equal(__parent_pointer& __parent, const _Key& __v) const {
1466      return const_cast<__tree*>(this)->__find_equal(__parent, __v);
1467    }
1468    template <class _Key>
1469    __node_base_pointer&
1470        __find_equal(const_iterator __hint, __parent_pointer& __parent,
1471                     __node_base_pointer& __dummy,
1472                     const _Key& __v);
1473
1474#ifndef _LIBCPP_CXX03_LANG
1475    template <class ..._Args>
1476    __node_holder __construct_node(_Args&& ...__args);
1477#else
1478    __node_holder __construct_node(const __container_value_type& __v);
1479#endif
1480
1481    void destroy(__node_pointer __nd) _NOEXCEPT;
1482
1483    _LIBCPP_INLINE_VISIBILITY
1484    void __copy_assign_alloc(const __tree& __t)
1485        {__copy_assign_alloc(__t, integral_constant<bool,
1486             __node_traits::propagate_on_container_copy_assignment::value>());}
1487
1488    _LIBCPP_INLINE_VISIBILITY
1489    void __copy_assign_alloc(const __tree& __t, true_type)
1490        {
1491        if (__node_alloc() != __t.__node_alloc())
1492            clear();
1493        __node_alloc() = __t.__node_alloc();
1494        }
1495    _LIBCPP_INLINE_VISIBILITY
1496    void __copy_assign_alloc(const __tree&, false_type) {}
1497
1498    void __move_assign(__tree& __t, false_type);
1499    void __move_assign(__tree& __t, true_type)
1500        _NOEXCEPT_(is_nothrow_move_assignable<value_compare>::value &&
1501                   is_nothrow_move_assignable<__node_allocator>::value);
1502
1503    _LIBCPP_INLINE_VISIBILITY
1504    void __move_assign_alloc(__tree& __t)
1505        _NOEXCEPT_(
1506            !__node_traits::propagate_on_container_move_assignment::value ||
1507            is_nothrow_move_assignable<__node_allocator>::value)
1508        {__move_assign_alloc(__t, integral_constant<bool,
1509             __node_traits::propagate_on_container_move_assignment::value>());}
1510
1511    _LIBCPP_INLINE_VISIBILITY
1512    void __move_assign_alloc(__tree& __t, true_type)
1513        _NOEXCEPT_(is_nothrow_move_assignable<__node_allocator>::value)
1514        {__node_alloc() = _VSTD::move(__t.__node_alloc());}
1515    _LIBCPP_INLINE_VISIBILITY
1516    void __move_assign_alloc(__tree&, false_type) _NOEXCEPT {}
1517
1518    struct _DetachedTreeCache {
1519      _LIBCPP_INLINE_VISIBILITY
1520      explicit _DetachedTreeCache(__tree *__t) _NOEXCEPT : __t_(__t),
1521        __cache_root_(__detach_from_tree(__t)) {
1522          __advance();
1523        }
1524
1525      _LIBCPP_INLINE_VISIBILITY
1526      __node_pointer __get() const _NOEXCEPT {
1527        return __cache_elem_;
1528      }
1529
1530      _LIBCPP_INLINE_VISIBILITY
1531      void __advance() _NOEXCEPT {
1532        __cache_elem_ = __cache_root_;
1533        if (__cache_root_) {
1534          __cache_root_ = __detach_next(__cache_root_);
1535        }
1536      }
1537
1538      _LIBCPP_INLINE_VISIBILITY
1539      ~_DetachedTreeCache() {
1540        __t_->destroy(__cache_elem_);
1541        if (__cache_root_) {
1542          while (__cache_root_->__parent_ != nullptr)
1543            __cache_root_ = static_cast<__node_pointer>(__cache_root_->__parent_);
1544          __t_->destroy(__cache_root_);
1545        }
1546      }
1547
1548       _DetachedTreeCache(_DetachedTreeCache const&) = delete;
1549       _DetachedTreeCache& operator=(_DetachedTreeCache const&) = delete;
1550
1551    private:
1552      _LIBCPP_INLINE_VISIBILITY
1553      static __node_pointer __detach_from_tree(__tree *__t) _NOEXCEPT;
1554      _LIBCPP_INLINE_VISIBILITY
1555      static __node_pointer __detach_next(__node_pointer) _NOEXCEPT;
1556
1557      __tree *__t_;
1558      __node_pointer __cache_root_;
1559      __node_pointer __cache_elem_;
1560    };
1561
1562
1563    template <class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS map;
1564    template <class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS multimap;
1565};
1566
1567template <class _Tp, class _Compare, class _Allocator>
1568__tree<_Tp, _Compare, _Allocator>::__tree(const value_compare& __comp)
1569        _NOEXCEPT_(
1570            is_nothrow_default_constructible<__node_allocator>::value &&
1571            is_nothrow_copy_constructible<value_compare>::value)
1572    : __pair3_(0, __comp)
1573{
1574    __begin_node() = __end_node();
1575}
1576
1577template <class _Tp, class _Compare, class _Allocator>
1578__tree<_Tp, _Compare, _Allocator>::__tree(const allocator_type& __a)
1579    : __begin_node_(__iter_pointer()),
1580      __pair1_(__default_init_tag(), __node_allocator(__a)),
1581      __pair3_(0, __default_init_tag())
1582{
1583    __begin_node() = __end_node();
1584}
1585
1586template <class _Tp, class _Compare, class _Allocator>
1587__tree<_Tp, _Compare, _Allocator>::__tree(const value_compare& __comp,
1588                                           const allocator_type& __a)
1589    : __begin_node_(__iter_pointer()),
1590      __pair1_(__default_init_tag(), __node_allocator(__a)),
1591      __pair3_(0, __comp)
1592{
1593    __begin_node() = __end_node();
1594}
1595
1596// Precondition:  size() != 0
1597template <class _Tp, class _Compare, class _Allocator>
1598typename __tree<_Tp, _Compare, _Allocator>::__node_pointer
1599__tree<_Tp, _Compare, _Allocator>::_DetachedTreeCache::__detach_from_tree(__tree *__t) _NOEXCEPT
1600{
1601    __node_pointer __cache = static_cast<__node_pointer>(__t->__begin_node());
1602    __t->__begin_node() = __t->__end_node();
1603    __t->__end_node()->__left_->__parent_ = nullptr;
1604    __t->__end_node()->__left_ = nullptr;
1605    __t->size() = 0;
1606    // __cache->__left_ == nullptr
1607    if (__cache->__right_ != nullptr)
1608        __cache = static_cast<__node_pointer>(__cache->__right_);
1609    // __cache->__left_ == nullptr
1610    // __cache->__right_ == nullptr
1611    return __cache;
1612}
1613
1614// Precondition:  __cache != nullptr
1615//    __cache->left_ == nullptr
1616//    __cache->right_ == nullptr
1617//    This is no longer a red-black tree
1618template <class _Tp, class _Compare, class _Allocator>
1619typename __tree<_Tp, _Compare, _Allocator>::__node_pointer
1620__tree<_Tp, _Compare, _Allocator>::_DetachedTreeCache::__detach_next(__node_pointer __cache) _NOEXCEPT
1621{
1622    if (__cache->__parent_ == nullptr)
1623        return nullptr;
1624    if (__tree_is_left_child(static_cast<__node_base_pointer>(__cache)))
1625    {
1626        __cache->__parent_->__left_ = nullptr;
1627        __cache = static_cast<__node_pointer>(__cache->__parent_);
1628        if (__cache->__right_ == nullptr)
1629            return __cache;
1630        return static_cast<__node_pointer>(__tree_leaf(__cache->__right_));
1631    }
1632    // __cache is right child
1633    __cache->__parent_unsafe()->__right_ = nullptr;
1634    __cache = static_cast<__node_pointer>(__cache->__parent_);
1635    if (__cache->__left_ == nullptr)
1636        return __cache;
1637    return static_cast<__node_pointer>(__tree_leaf(__cache->__left_));
1638}
1639
1640template <class _Tp, class _Compare, class _Allocator>
1641__tree<_Tp, _Compare, _Allocator>&
1642__tree<_Tp, _Compare, _Allocator>::operator=(const __tree& __t)
1643{
1644    if (this != &__t)
1645    {
1646        value_comp() = __t.value_comp();
1647        __copy_assign_alloc(__t);
1648        __assign_multi(__t.begin(), __t.end());
1649    }
1650    return *this;
1651}
1652
1653template <class _Tp, class _Compare, class _Allocator>
1654template <class _ForwardIterator>
1655void
1656__tree<_Tp, _Compare, _Allocator>::__assign_unique(_ForwardIterator __first, _ForwardIterator __last)
1657{
1658    typedef iterator_traits<_ForwardIterator> _ITraits;
1659    typedef typename _ITraits::value_type _ItValueType;
1660    static_assert((is_same<_ItValueType, __container_value_type>::value),
1661                  "__assign_unique may only be called with the containers value type");
1662    static_assert(__is_cpp17_forward_iterator<_ForwardIterator>::value,
1663                  "__assign_unique requires a forward iterator");
1664    if (size() != 0)
1665    {
1666        _DetachedTreeCache __cache(this);
1667          for (; __cache.__get() != nullptr && __first != __last; ++__first) {
1668              if (__node_assign_unique(*__first, __cache.__get()).second)
1669                  __cache.__advance();
1670            }
1671    }
1672    for (; __first != __last; ++__first)
1673        __insert_unique(*__first);
1674}
1675
1676template <class _Tp, class _Compare, class _Allocator>
1677template <class _InputIterator>
1678void
1679__tree<_Tp, _Compare, _Allocator>::__assign_multi(_InputIterator __first, _InputIterator __last)
1680{
1681    typedef iterator_traits<_InputIterator> _ITraits;
1682    typedef typename _ITraits::value_type _ItValueType;
1683    static_assert((is_same<_ItValueType, __container_value_type>::value ||
1684                  is_same<_ItValueType, __node_value_type>::value),
1685                  "__assign_multi may only be called with the containers value type"
1686                  " or the nodes value type");
1687    if (size() != 0)
1688    {
1689        _DetachedTreeCache __cache(this);
1690        for (; __cache.__get() && __first != __last; ++__first) {
1691            __cache.__get()->__value_ = *__first;
1692            __node_insert_multi(__cache.__get());
1693            __cache.__advance();
1694        }
1695    }
1696    for (; __first != __last; ++__first)
1697        __insert_multi(_NodeTypes::__get_value(*__first));
1698}
1699
1700template <class _Tp, class _Compare, class _Allocator>
1701__tree<_Tp, _Compare, _Allocator>::__tree(const __tree& __t)
1702    : __begin_node_(__iter_pointer()),
1703      __pair1_(__default_init_tag(), __node_traits::select_on_container_copy_construction(__t.__node_alloc())),
1704      __pair3_(0, __t.value_comp())
1705{
1706    __begin_node() = __end_node();
1707}
1708
1709#ifndef _LIBCPP_CXX03_LANG
1710
1711template <class _Tp, class _Compare, class _Allocator>
1712__tree<_Tp, _Compare, _Allocator>::__tree(__tree&& __t)
1713    _NOEXCEPT_(
1714        is_nothrow_move_constructible<__node_allocator>::value &&
1715        is_nothrow_move_constructible<value_compare>::value)
1716    : __begin_node_(_VSTD::move(__t.__begin_node_)),
1717      __pair1_(_VSTD::move(__t.__pair1_)),
1718      __pair3_(_VSTD::move(__t.__pair3_))
1719{
1720    if (size() == 0)
1721        __begin_node() = __end_node();
1722    else
1723    {
1724        __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
1725        __t.__begin_node() = __t.__end_node();
1726        __t.__end_node()->__left_ = nullptr;
1727        __t.size() = 0;
1728    }
1729}
1730
1731template <class _Tp, class _Compare, class _Allocator>
1732__tree<_Tp, _Compare, _Allocator>::__tree(__tree&& __t, const allocator_type& __a)
1733    : __pair1_(__default_init_tag(), __node_allocator(__a)),
1734      __pair3_(0, _VSTD::move(__t.value_comp()))
1735{
1736    if (__a == __t.__alloc())
1737    {
1738        if (__t.size() == 0)
1739            __begin_node() = __end_node();
1740        else
1741        {
1742            __begin_node() = __t.__begin_node();
1743            __end_node()->__left_ = __t.__end_node()->__left_;
1744            __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
1745            size() = __t.size();
1746            __t.__begin_node() = __t.__end_node();
1747            __t.__end_node()->__left_ = nullptr;
1748            __t.size() = 0;
1749        }
1750    }
1751    else
1752    {
1753        __begin_node() = __end_node();
1754    }
1755}
1756
1757template <class _Tp, class _Compare, class _Allocator>
1758void
1759__tree<_Tp, _Compare, _Allocator>::__move_assign(__tree& __t, true_type)
1760    _NOEXCEPT_(is_nothrow_move_assignable<value_compare>::value &&
1761               is_nothrow_move_assignable<__node_allocator>::value)
1762{
1763    destroy(static_cast<__node_pointer>(__end_node()->__left_));
1764    __begin_node_ = __t.__begin_node_;
1765    __pair1_.first() = __t.__pair1_.first();
1766    __move_assign_alloc(__t);
1767    __pair3_ = _VSTD::move(__t.__pair3_);
1768    if (size() == 0)
1769        __begin_node() = __end_node();
1770    else
1771    {
1772        __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
1773        __t.__begin_node() = __t.__end_node();
1774        __t.__end_node()->__left_ = nullptr;
1775        __t.size() = 0;
1776    }
1777}
1778
1779template <class _Tp, class _Compare, class _Allocator>
1780void
1781__tree<_Tp, _Compare, _Allocator>::__move_assign(__tree& __t, false_type)
1782{
1783    if (__node_alloc() == __t.__node_alloc())
1784        __move_assign(__t, true_type());
1785    else
1786    {
1787        value_comp() = _VSTD::move(__t.value_comp());
1788        const_iterator __e = end();
1789        if (size() != 0)
1790        {
1791            _DetachedTreeCache __cache(this);
1792            while (__cache.__get() != nullptr && __t.size() != 0) {
1793              __cache.__get()->__value_ = _VSTD::move(__t.remove(__t.begin())->__value_);
1794              __node_insert_multi(__cache.__get());
1795              __cache.__advance();
1796            }
1797        }
1798        while (__t.size() != 0)
1799            __insert_multi(__e, _NodeTypes::__move(__t.remove(__t.begin())->__value_));
1800    }
1801}
1802
1803template <class _Tp, class _Compare, class _Allocator>
1804__tree<_Tp, _Compare, _Allocator>&
1805__tree<_Tp, _Compare, _Allocator>::operator=(__tree&& __t)
1806    _NOEXCEPT_(
1807        __node_traits::propagate_on_container_move_assignment::value &&
1808        is_nothrow_move_assignable<value_compare>::value &&
1809        is_nothrow_move_assignable<__node_allocator>::value)
1810
1811{
1812    __move_assign(__t, integral_constant<bool,
1813                  __node_traits::propagate_on_container_move_assignment::value>());
1814    return *this;
1815}
1816
1817#endif  // _LIBCPP_CXX03_LANG
1818
1819template <class _Tp, class _Compare, class _Allocator>
1820__tree<_Tp, _Compare, _Allocator>::~__tree()
1821{
1822    static_assert((is_copy_constructible<value_compare>::value),
1823                 "Comparator must be copy-constructible.");
1824  destroy(__root());
1825}
1826
1827template <class _Tp, class _Compare, class _Allocator>
1828void
1829__tree<_Tp, _Compare, _Allocator>::destroy(__node_pointer __nd) _NOEXCEPT
1830{
1831    if (__nd != nullptr)
1832    {
1833        destroy(static_cast<__node_pointer>(__nd->__left_));
1834        destroy(static_cast<__node_pointer>(__nd->__right_));
1835        __node_allocator& __na = __node_alloc();
1836        __node_traits::destroy(__na, _NodeTypes::__get_ptr(__nd->__value_));
1837        __node_traits::deallocate(__na, __nd, 1);
1838    }
1839}
1840
1841template <class _Tp, class _Compare, class _Allocator>
1842void
1843__tree<_Tp, _Compare, _Allocator>::swap(__tree& __t)
1844#if _LIBCPP_STD_VER <= 11
1845        _NOEXCEPT_(
1846            __is_nothrow_swappable<value_compare>::value
1847            && (!__node_traits::propagate_on_container_swap::value ||
1848                 __is_nothrow_swappable<__node_allocator>::value)
1849            )
1850#else
1851        _NOEXCEPT_(__is_nothrow_swappable<value_compare>::value)
1852#endif
1853{
1854    using _VSTD::swap;
1855    swap(__begin_node_, __t.__begin_node_);
1856    swap(__pair1_.first(), __t.__pair1_.first());
1857    __swap_allocator(__node_alloc(), __t.__node_alloc());
1858    __pair3_.swap(__t.__pair3_);
1859    if (size() == 0)
1860        __begin_node() = __end_node();
1861    else
1862        __end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__end_node());
1863    if (__t.size() == 0)
1864        __t.__begin_node() = __t.__end_node();
1865    else
1866        __t.__end_node()->__left_->__parent_ = static_cast<__parent_pointer>(__t.__end_node());
1867}
1868
1869template <class _Tp, class _Compare, class _Allocator>
1870void
1871__tree<_Tp, _Compare, _Allocator>::clear() _NOEXCEPT
1872{
1873    destroy(__root());
1874    size() = 0;
1875    __begin_node() = __end_node();
1876    __end_node()->__left_ = nullptr;
1877}
1878
1879// Find lower_bound place to insert
1880// Set __parent to parent of null leaf
1881// Return reference to null leaf
1882template <class _Tp, class _Compare, class _Allocator>
1883typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
1884__tree<_Tp, _Compare, _Allocator>::__find_leaf_low(__parent_pointer& __parent,
1885                                                   const key_type& __v)
1886{
1887    __node_pointer __nd = __root();
1888    if (__nd != nullptr)
1889    {
1890        while (true)
1891        {
1892            if (value_comp()(__nd->__value_, __v))
1893            {
1894                if (__nd->__right_ != nullptr)
1895                    __nd = static_cast<__node_pointer>(__nd->__right_);
1896                else
1897                {
1898                    __parent = static_cast<__parent_pointer>(__nd);
1899                    return __nd->__right_;
1900                }
1901            }
1902            else
1903            {
1904                if (__nd->__left_ != nullptr)
1905                    __nd = static_cast<__node_pointer>(__nd->__left_);
1906                else
1907                {
1908                    __parent = static_cast<__parent_pointer>(__nd);
1909                    return __parent->__left_;
1910                }
1911            }
1912        }
1913    }
1914    __parent = static_cast<__parent_pointer>(__end_node());
1915    return __parent->__left_;
1916}
1917
1918// Find upper_bound place to insert
1919// Set __parent to parent of null leaf
1920// Return reference to null leaf
1921template <class _Tp, class _Compare, class _Allocator>
1922typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
1923__tree<_Tp, _Compare, _Allocator>::__find_leaf_high(__parent_pointer& __parent,
1924                                                    const key_type& __v)
1925{
1926    __node_pointer __nd = __root();
1927    if (__nd != nullptr)
1928    {
1929        while (true)
1930        {
1931            if (value_comp()(__v, __nd->__value_))
1932            {
1933                if (__nd->__left_ != nullptr)
1934                    __nd = static_cast<__node_pointer>(__nd->__left_);
1935                else
1936                {
1937                    __parent = static_cast<__parent_pointer>(__nd);
1938                    return __parent->__left_;
1939                }
1940            }
1941            else
1942            {
1943                if (__nd->__right_ != nullptr)
1944                    __nd = static_cast<__node_pointer>(__nd->__right_);
1945                else
1946                {
1947                    __parent = static_cast<__parent_pointer>(__nd);
1948                    return __nd->__right_;
1949                }
1950            }
1951        }
1952    }
1953    __parent = static_cast<__parent_pointer>(__end_node());
1954    return __parent->__left_;
1955}
1956
1957// Find leaf place to insert closest to __hint
1958// First check prior to __hint.
1959// Next check after __hint.
1960// Next do O(log N) search.
1961// Set __parent to parent of null leaf
1962// Return reference to null leaf
1963template <class _Tp, class _Compare, class _Allocator>
1964typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
1965__tree<_Tp, _Compare, _Allocator>::__find_leaf(const_iterator __hint,
1966                                               __parent_pointer& __parent,
1967                                               const key_type& __v)
1968{
1969    if (__hint == end() || !value_comp()(*__hint, __v))  // check before
1970    {
1971        // __v <= *__hint
1972        const_iterator __prior = __hint;
1973        if (__prior == begin() || !value_comp()(__v, *--__prior))
1974        {
1975            // *prev(__hint) <= __v <= *__hint
1976            if (__hint.__ptr_->__left_ == nullptr)
1977            {
1978                __parent = static_cast<__parent_pointer>(__hint.__ptr_);
1979                return __parent->__left_;
1980            }
1981            else
1982            {
1983                __parent = static_cast<__parent_pointer>(__prior.__ptr_);
1984                return static_cast<__node_base_pointer>(__prior.__ptr_)->__right_;
1985            }
1986        }
1987        // __v < *prev(__hint)
1988        return __find_leaf_high(__parent, __v);
1989    }
1990    // else __v > *__hint
1991    return __find_leaf_low(__parent, __v);
1992}
1993
1994// Find place to insert if __v doesn't exist
1995// Set __parent to parent of null leaf
1996// Return reference to null leaf
1997// If __v exists, set parent to node of __v and return reference to node of __v
1998template <class _Tp, class _Compare, class _Allocator>
1999template <class _Key>
2000typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
2001__tree<_Tp, _Compare, _Allocator>::__find_equal(__parent_pointer& __parent,
2002                                                const _Key& __v)
2003{
2004    __node_pointer __nd = __root();
2005    __node_base_pointer* __nd_ptr = __root_ptr();
2006    if (__nd != nullptr)
2007    {
2008        while (true)
2009        {
2010            if (value_comp()(__v, __nd->__value_))
2011            {
2012                if (__nd->__left_ != nullptr) {
2013                    __nd_ptr = _VSTD::addressof(__nd->__left_);
2014                    __nd = static_cast<__node_pointer>(__nd->__left_);
2015                } else {
2016                    __parent = static_cast<__parent_pointer>(__nd);
2017                    return __parent->__left_;
2018                }
2019            }
2020            else if (value_comp()(__nd->__value_, __v))
2021            {
2022                if (__nd->__right_ != nullptr) {
2023                    __nd_ptr = _VSTD::addressof(__nd->__right_);
2024                    __nd = static_cast<__node_pointer>(__nd->__right_);
2025                } else {
2026                    __parent = static_cast<__parent_pointer>(__nd);
2027                    return __nd->__right_;
2028                }
2029            }
2030            else
2031            {
2032                __parent = static_cast<__parent_pointer>(__nd);
2033                return *__nd_ptr;
2034            }
2035        }
2036    }
2037    __parent = static_cast<__parent_pointer>(__end_node());
2038    return __parent->__left_;
2039}
2040
2041// Find place to insert if __v doesn't exist
2042// First check prior to __hint.
2043// Next check after __hint.
2044// Next do O(log N) search.
2045// Set __parent to parent of null leaf
2046// Return reference to null leaf
2047// If __v exists, set parent to node of __v and return reference to node of __v
2048template <class _Tp, class _Compare, class _Allocator>
2049template <class _Key>
2050typename __tree<_Tp, _Compare, _Allocator>::__node_base_pointer&
2051__tree<_Tp, _Compare, _Allocator>::__find_equal(const_iterator __hint,
2052                                                __parent_pointer& __parent,
2053                                                __node_base_pointer& __dummy,
2054                                                const _Key& __v)
2055{
2056    if (__hint == end() || value_comp()(__v, *__hint))  // check before
2057    {
2058        // __v < *__hint
2059        const_iterator __prior = __hint;
2060        if (__prior == begin() || value_comp()(*--__prior, __v))
2061        {
2062            // *prev(__hint) < __v < *__hint
2063            if (__hint.__ptr_->__left_ == nullptr)
2064            {
2065                __parent = static_cast<__parent_pointer>(__hint.__ptr_);
2066                return __parent->__left_;
2067            }
2068            else
2069            {
2070                __parent = static_cast<__parent_pointer>(__prior.__ptr_);
2071                return static_cast<__node_base_pointer>(__prior.__ptr_)->__right_;
2072            }
2073        }
2074        // __v <= *prev(__hint)
2075        return __find_equal(__parent, __v);
2076    }
2077    else if (value_comp()(*__hint, __v))  // check after
2078    {
2079        // *__hint < __v
2080        const_iterator __next = _VSTD::next(__hint);
2081        if (__next == end() || value_comp()(__v, *__next))
2082        {
2083            // *__hint < __v < *_VSTD::next(__hint)
2084            if (__hint.__get_np()->__right_ == nullptr)
2085            {
2086                __parent = static_cast<__parent_pointer>(__hint.__ptr_);
2087                return static_cast<__node_base_pointer>(__hint.__ptr_)->__right_;
2088            }
2089            else
2090            {
2091                __parent = static_cast<__parent_pointer>(__next.__ptr_);
2092                return __parent->__left_;
2093            }
2094        }
2095        // *next(__hint) <= __v
2096        return __find_equal(__parent, __v);
2097    }
2098    // else __v == *__hint
2099    __parent = static_cast<__parent_pointer>(__hint.__ptr_);
2100    __dummy = static_cast<__node_base_pointer>(__hint.__ptr_);
2101    return __dummy;
2102}
2103
2104template <class _Tp, class _Compare, class _Allocator>
2105void __tree<_Tp, _Compare, _Allocator>::__insert_node_at(
2106    __parent_pointer __parent, __node_base_pointer& __child,
2107    __node_base_pointer __new_node) _NOEXCEPT
2108{
2109    __new_node->__left_   = nullptr;
2110    __new_node->__right_  = nullptr;
2111    __new_node->__parent_ = __parent;
2112    // __new_node->__is_black_ is initialized in __tree_balance_after_insert
2113    __child = __new_node;
2114    if (__begin_node()->__left_ != nullptr)
2115        __begin_node() = static_cast<__iter_pointer>(__begin_node()->__left_);
2116    __tree_balance_after_insert(__end_node()->__left_, __child);
2117    ++size();
2118}
2119
2120#ifndef _LIBCPP_CXX03_LANG
2121template <class _Tp, class _Compare, class _Allocator>
2122template <class _Key, class... _Args>
2123pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
2124__tree<_Tp, _Compare, _Allocator>::__emplace_unique_key_args(_Key const& __k, _Args&&... __args)
2125#else
2126template <class _Tp, class _Compare, class _Allocator>
2127template <class _Key, class _Args>
2128pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
2129__tree<_Tp, _Compare, _Allocator>::__emplace_unique_key_args(_Key const& __k, _Args& __args)
2130#endif
2131{
2132    __parent_pointer __parent;
2133    __node_base_pointer& __child = __find_equal(__parent, __k);
2134    __node_pointer __r = static_cast<__node_pointer>(__child);
2135    bool __inserted = false;
2136    if (__child == nullptr)
2137    {
2138#ifndef _LIBCPP_CXX03_LANG
2139        __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2140#else
2141        __node_holder __h = __construct_node(__args);
2142#endif
2143        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2144        __r = __h.release();
2145        __inserted = true;
2146    }
2147    return pair<iterator, bool>(iterator(__r), __inserted);
2148}
2149
2150
2151#ifndef _LIBCPP_CXX03_LANG
2152template <class _Tp, class _Compare, class _Allocator>
2153template <class _Key, class... _Args>
2154typename __tree<_Tp, _Compare, _Allocator>::iterator
2155__tree<_Tp, _Compare, _Allocator>::__emplace_hint_unique_key_args(
2156    const_iterator __p, _Key const& __k, _Args&&... __args)
2157#else
2158template <class _Tp, class _Compare, class _Allocator>
2159template <class _Key, class _Args>
2160typename __tree<_Tp, _Compare, _Allocator>::iterator
2161__tree<_Tp, _Compare, _Allocator>::__emplace_hint_unique_key_args(
2162    const_iterator __p, _Key const& __k, _Args& __args)
2163#endif
2164{
2165    __parent_pointer __parent;
2166    __node_base_pointer __dummy;
2167    __node_base_pointer& __child = __find_equal(__p, __parent, __dummy, __k);
2168    __node_pointer __r = static_cast<__node_pointer>(__child);
2169    if (__child == nullptr)
2170    {
2171#ifndef _LIBCPP_CXX03_LANG
2172        __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2173#else
2174        __node_holder __h = __construct_node(__args);
2175#endif
2176        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2177        __r = __h.release();
2178    }
2179    return iterator(__r);
2180}
2181
2182
2183#ifndef _LIBCPP_CXX03_LANG
2184
2185template <class _Tp, class _Compare, class _Allocator>
2186template <class ..._Args>
2187typename __tree<_Tp, _Compare, _Allocator>::__node_holder
2188__tree<_Tp, _Compare, _Allocator>::__construct_node(_Args&& ...__args)
2189{
2190    static_assert(!__is_tree_value_type<_Args...>::value,
2191                  "Cannot construct from __value_type");
2192    __node_allocator& __na = __node_alloc();
2193    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
2194    __node_traits::construct(__na, _NodeTypes::__get_ptr(__h->__value_), _VSTD::forward<_Args>(__args)...);
2195    __h.get_deleter().__value_constructed = true;
2196    return __h;
2197}
2198
2199
2200template <class _Tp, class _Compare, class _Allocator>
2201template <class... _Args>
2202pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
2203__tree<_Tp, _Compare, _Allocator>::__emplace_unique_impl(_Args&&... __args)
2204{
2205    __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2206    __parent_pointer __parent;
2207    __node_base_pointer& __child = __find_equal(__parent, __h->__value_);
2208    __node_pointer __r = static_cast<__node_pointer>(__child);
2209    bool __inserted = false;
2210    if (__child == nullptr)
2211    {
2212        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2213        __r = __h.release();
2214        __inserted = true;
2215    }
2216    return pair<iterator, bool>(iterator(__r), __inserted);
2217}
2218
2219template <class _Tp, class _Compare, class _Allocator>
2220template <class... _Args>
2221typename __tree<_Tp, _Compare, _Allocator>::iterator
2222__tree<_Tp, _Compare, _Allocator>::__emplace_hint_unique_impl(const_iterator __p, _Args&&... __args)
2223{
2224    __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2225    __parent_pointer __parent;
2226    __node_base_pointer __dummy;
2227    __node_base_pointer& __child = __find_equal(__p, __parent, __dummy, __h->__value_);
2228    __node_pointer __r = static_cast<__node_pointer>(__child);
2229    if (__child == nullptr)
2230    {
2231        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2232        __r = __h.release();
2233    }
2234    return iterator(__r);
2235}
2236
2237template <class _Tp, class _Compare, class _Allocator>
2238template <class... _Args>
2239typename __tree<_Tp, _Compare, _Allocator>::iterator
2240__tree<_Tp, _Compare, _Allocator>::__emplace_multi(_Args&&... __args)
2241{
2242    __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2243    __parent_pointer __parent;
2244    __node_base_pointer& __child = __find_leaf_high(__parent, _NodeTypes::__get_key(__h->__value_));
2245    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2246    return iterator(static_cast<__node_pointer>(__h.release()));
2247}
2248
2249template <class _Tp, class _Compare, class _Allocator>
2250template <class... _Args>
2251typename __tree<_Tp, _Compare, _Allocator>::iterator
2252__tree<_Tp, _Compare, _Allocator>::__emplace_hint_multi(const_iterator __p,
2253                                                        _Args&&... __args)
2254{
2255    __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
2256    __parent_pointer __parent;
2257    __node_base_pointer& __child = __find_leaf(__p, __parent, _NodeTypes::__get_key(__h->__value_));
2258    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2259    return iterator(static_cast<__node_pointer>(__h.release()));
2260}
2261
2262
2263#else  // _LIBCPP_CXX03_LANG
2264
2265template <class _Tp, class _Compare, class _Allocator>
2266typename __tree<_Tp, _Compare, _Allocator>::__node_holder
2267__tree<_Tp, _Compare, _Allocator>::__construct_node(const __container_value_type& __v)
2268{
2269    __node_allocator& __na = __node_alloc();
2270    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
2271    __node_traits::construct(__na, _NodeTypes::__get_ptr(__h->__value_), __v);
2272    __h.get_deleter().__value_constructed = true;
2273    return _LIBCPP_EXPLICIT_MOVE(__h);  // explicitly moved for C++03
2274}
2275
2276#endif  // _LIBCPP_CXX03_LANG
2277
2278#ifdef _LIBCPP_CXX03_LANG
2279template <class _Tp, class _Compare, class _Allocator>
2280typename __tree<_Tp, _Compare, _Allocator>::iterator
2281__tree<_Tp, _Compare, _Allocator>::__insert_multi(const __container_value_type& __v)
2282{
2283    __parent_pointer __parent;
2284    __node_base_pointer& __child = __find_leaf_high(__parent, _NodeTypes::__get_key(__v));
2285    __node_holder __h = __construct_node(__v);
2286    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2287    return iterator(__h.release());
2288}
2289
2290template <class _Tp, class _Compare, class _Allocator>
2291typename __tree<_Tp, _Compare, _Allocator>::iterator
2292__tree<_Tp, _Compare, _Allocator>::__insert_multi(const_iterator __p, const __container_value_type& __v)
2293{
2294    __parent_pointer __parent;
2295    __node_base_pointer& __child = __find_leaf(__p, __parent, _NodeTypes::__get_key(__v));
2296    __node_holder __h = __construct_node(__v);
2297    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
2298    return iterator(__h.release());
2299}
2300#endif
2301
2302template <class _Tp, class _Compare, class _Allocator>
2303pair<typename __tree<_Tp, _Compare, _Allocator>::iterator, bool>
2304__tree<_Tp, _Compare, _Allocator>::__node_assign_unique(const __container_value_type& __v, __node_pointer __nd)
2305{
2306    __parent_pointer __parent;
2307    __node_base_pointer& __child = __find_equal(__parent, _NodeTypes::__get_key(__v));
2308    __node_pointer __r = static_cast<__node_pointer>(__child);
2309    bool __inserted = false;
2310    if (__child == nullptr)
2311    {
2312        __nd->__value_ = __v;
2313        __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
2314        __r = __nd;
2315        __inserted = true;
2316    }
2317    return pair<iterator, bool>(iterator(__r), __inserted);
2318}
2319
2320
2321template <class _Tp, class _Compare, class _Allocator>
2322typename __tree<_Tp, _Compare, _Allocator>::iterator
2323__tree<_Tp, _Compare, _Allocator>::__node_insert_multi(__node_pointer __nd)
2324{
2325    __parent_pointer __parent;
2326    __node_base_pointer& __child = __find_leaf_high(__parent, _NodeTypes::__get_key(__nd->__value_));
2327    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
2328    return iterator(__nd);
2329}
2330
2331template <class _Tp, class _Compare, class _Allocator>
2332typename __tree<_Tp, _Compare, _Allocator>::iterator
2333__tree<_Tp, _Compare, _Allocator>::__node_insert_multi(const_iterator __p,
2334                                                       __node_pointer __nd)
2335{
2336    __parent_pointer __parent;
2337    __node_base_pointer& __child = __find_leaf(__p, __parent, _NodeTypes::__get_key(__nd->__value_));
2338    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__nd));
2339    return iterator(__nd);
2340}
2341
2342template <class _Tp, class _Compare, class _Allocator>
2343typename __tree<_Tp, _Compare, _Allocator>::iterator
2344__tree<_Tp, _Compare, _Allocator>::__remove_node_pointer(__node_pointer __ptr) _NOEXCEPT
2345{
2346    iterator __r(__ptr);
2347    ++__r;
2348    if (__begin_node() == __ptr)
2349        __begin_node() = __r.__ptr_;
2350    --size();
2351    __tree_remove(__end_node()->__left_,
2352                  static_cast<__node_base_pointer>(__ptr));
2353    return __r;
2354}
2355
2356#if _LIBCPP_STD_VER > 14
2357template <class _Tp, class _Compare, class _Allocator>
2358template <class _NodeHandle, class _InsertReturnType>
2359_LIBCPP_INLINE_VISIBILITY
2360_InsertReturnType
2361__tree<_Tp, _Compare, _Allocator>::__node_handle_insert_unique(
2362    _NodeHandle&& __nh)
2363{
2364    if (__nh.empty())
2365        return _InsertReturnType{end(), false, _NodeHandle()};
2366
2367    __node_pointer __ptr = __nh.__ptr_;
2368    __parent_pointer __parent;
2369    __node_base_pointer& __child = __find_equal(__parent,
2370                                                __ptr->__value_);
2371    if (__child != nullptr)
2372        return _InsertReturnType{
2373            iterator(static_cast<__node_pointer>(__child)),
2374            false, _VSTD::move(__nh)};
2375
2376    __insert_node_at(__parent, __child,
2377                     static_cast<__node_base_pointer>(__ptr));
2378    __nh.__release_ptr();
2379    return _InsertReturnType{iterator(__ptr), true, _NodeHandle()};
2380}
2381
2382template <class _Tp, class _Compare, class _Allocator>
2383template <class _NodeHandle>
2384_LIBCPP_INLINE_VISIBILITY
2385typename __tree<_Tp, _Compare, _Allocator>::iterator
2386__tree<_Tp, _Compare, _Allocator>::__node_handle_insert_unique(
2387    const_iterator __hint, _NodeHandle&& __nh)
2388{
2389    if (__nh.empty())
2390        return end();
2391
2392    __node_pointer __ptr = __nh.__ptr_;
2393    __parent_pointer __parent;
2394    __node_base_pointer __dummy;
2395    __node_base_pointer& __child = __find_equal(__hint, __parent, __dummy,
2396                                                __ptr->__value_);
2397    __node_pointer __r = static_cast<__node_pointer>(__child);
2398    if (__child == nullptr)
2399    {
2400        __insert_node_at(__parent, __child,
2401                         static_cast<__node_base_pointer>(__ptr));
2402        __r = __ptr;
2403        __nh.__release_ptr();
2404    }
2405    return iterator(__r);
2406}
2407
2408template <class _Tp, class _Compare, class _Allocator>
2409template <class _NodeHandle>
2410_LIBCPP_INLINE_VISIBILITY
2411_NodeHandle
2412__tree<_Tp, _Compare, _Allocator>::__node_handle_extract(key_type const& __key)
2413{
2414    iterator __it = find(__key);
2415    if (__it == end())
2416        return _NodeHandle();
2417    return __node_handle_extract<_NodeHandle>(__it);
2418}
2419
2420template <class _Tp, class _Compare, class _Allocator>
2421template <class _NodeHandle>
2422_LIBCPP_INLINE_VISIBILITY
2423_NodeHandle
2424__tree<_Tp, _Compare, _Allocator>::__node_handle_extract(const_iterator __p)
2425{
2426    __node_pointer __np = __p.__get_np();
2427    __remove_node_pointer(__np);
2428    return _NodeHandle(__np, __alloc());
2429}
2430
2431template <class _Tp, class _Compare, class _Allocator>
2432template <class _Tree>
2433_LIBCPP_INLINE_VISIBILITY
2434void
2435__tree<_Tp, _Compare, _Allocator>::__node_handle_merge_unique(_Tree& __source)
2436{
2437    static_assert(is_same<typename _Tree::__node_pointer, __node_pointer>::value, "");
2438
2439    for (typename _Tree::iterator __i = __source.begin();
2440         __i != __source.end();)
2441    {
2442        __node_pointer __src_ptr = __i.__get_np();
2443        __parent_pointer __parent;
2444        __node_base_pointer& __child =
2445            __find_equal(__parent, _NodeTypes::__get_key(__src_ptr->__value_));
2446        ++__i;
2447        if (__child != nullptr)
2448            continue;
2449        __source.__remove_node_pointer(__src_ptr);
2450        __insert_node_at(__parent, __child,
2451                         static_cast<__node_base_pointer>(__src_ptr));
2452    }
2453}
2454
2455template <class _Tp, class _Compare, class _Allocator>
2456template <class _NodeHandle>
2457_LIBCPP_INLINE_VISIBILITY
2458typename __tree<_Tp, _Compare, _Allocator>::iterator
2459__tree<_Tp, _Compare, _Allocator>::__node_handle_insert_multi(_NodeHandle&& __nh)
2460{
2461    if (__nh.empty())
2462        return end();
2463    __node_pointer __ptr = __nh.__ptr_;
2464    __parent_pointer __parent;
2465    __node_base_pointer& __child = __find_leaf_high(
2466        __parent, _NodeTypes::__get_key(__ptr->__value_));
2467    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__ptr));
2468    __nh.__release_ptr();
2469    return iterator(__ptr);
2470}
2471
2472template <class _Tp, class _Compare, class _Allocator>
2473template <class _NodeHandle>
2474_LIBCPP_INLINE_VISIBILITY
2475typename __tree<_Tp, _Compare, _Allocator>::iterator
2476__tree<_Tp, _Compare, _Allocator>::__node_handle_insert_multi(
2477    const_iterator __hint, _NodeHandle&& __nh)
2478{
2479    if (__nh.empty())
2480        return end();
2481
2482    __node_pointer __ptr = __nh.__ptr_;
2483    __parent_pointer __parent;
2484    __node_base_pointer& __child = __find_leaf(__hint, __parent,
2485                                               _NodeTypes::__get_key(__ptr->__value_));
2486    __insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__ptr));
2487    __nh.__release_ptr();
2488    return iterator(__ptr);
2489}
2490
2491template <class _Tp, class _Compare, class _Allocator>
2492template <class _Tree>
2493_LIBCPP_INLINE_VISIBILITY
2494void
2495__tree<_Tp, _Compare, _Allocator>::__node_handle_merge_multi(_Tree& __source)
2496{
2497    static_assert(is_same<typename _Tree::__node_pointer, __node_pointer>::value, "");
2498
2499    for (typename _Tree::iterator __i = __source.begin();
2500         __i != __source.end();)
2501    {
2502        __node_pointer __src_ptr = __i.__get_np();
2503        __parent_pointer __parent;
2504        __node_base_pointer& __child = __find_leaf_high(
2505            __parent, _NodeTypes::__get_key(__src_ptr->__value_));
2506        ++__i;
2507        __source.__remove_node_pointer(__src_ptr);
2508        __insert_node_at(__parent, __child,
2509                         static_cast<__node_base_pointer>(__src_ptr));
2510    }
2511}
2512
2513#endif  // _LIBCPP_STD_VER > 14
2514
2515template <class _Tp, class _Compare, class _Allocator>
2516typename __tree<_Tp, _Compare, _Allocator>::iterator
2517__tree<_Tp, _Compare, _Allocator>::erase(const_iterator __p)
2518{
2519    __node_pointer __np = __p.__get_np();
2520    iterator __r = __remove_node_pointer(__np);
2521    __node_allocator& __na = __node_alloc();
2522    __node_traits::destroy(__na, _NodeTypes::__get_ptr(
2523        const_cast<__node_value_type&>(*__p)));
2524    __node_traits::deallocate(__na, __np, 1);
2525    return __r;
2526}
2527
2528template <class _Tp, class _Compare, class _Allocator>
2529typename __tree<_Tp, _Compare, _Allocator>::iterator
2530__tree<_Tp, _Compare, _Allocator>::erase(const_iterator __f, const_iterator __l)
2531{
2532    while (__f != __l)
2533        __f = erase(__f);
2534    return iterator(__l.__ptr_);
2535}
2536
2537template <class _Tp, class _Compare, class _Allocator>
2538template <class _Key>
2539typename __tree<_Tp, _Compare, _Allocator>::size_type
2540__tree<_Tp, _Compare, _Allocator>::__erase_unique(const _Key& __k)
2541{
2542    iterator __i = find(__k);
2543    if (__i == end())
2544        return 0;
2545    erase(__i);
2546    return 1;
2547}
2548
2549template <class _Tp, class _Compare, class _Allocator>
2550template <class _Key>
2551typename __tree<_Tp, _Compare, _Allocator>::size_type
2552__tree<_Tp, _Compare, _Allocator>::__erase_multi(const _Key& __k)
2553{
2554    pair<iterator, iterator> __p = __equal_range_multi(__k);
2555    size_type __r = 0;
2556    for (; __p.first != __p.second; ++__r)
2557        __p.first = erase(__p.first);
2558    return __r;
2559}
2560
2561template <class _Tp, class _Compare, class _Allocator>
2562template <class _Key>
2563typename __tree<_Tp, _Compare, _Allocator>::iterator
2564__tree<_Tp, _Compare, _Allocator>::find(const _Key& __v)
2565{
2566    iterator __p = __lower_bound(__v, __root(), __end_node());
2567    if (__p != end() && !value_comp()(__v, *__p))
2568        return __p;
2569    return end();
2570}
2571
2572template <class _Tp, class _Compare, class _Allocator>
2573template <class _Key>
2574typename __tree<_Tp, _Compare, _Allocator>::const_iterator
2575__tree<_Tp, _Compare, _Allocator>::find(const _Key& __v) const
2576{
2577    const_iterator __p = __lower_bound(__v, __root(), __end_node());
2578    if (__p != end() && !value_comp()(__v, *__p))
2579        return __p;
2580    return end();
2581}
2582
2583template <class _Tp, class _Compare, class _Allocator>
2584template <class _Key>
2585typename __tree<_Tp, _Compare, _Allocator>::size_type
2586__tree<_Tp, _Compare, _Allocator>::__count_unique(const _Key& __k) const
2587{
2588    __node_pointer __rt = __root();
2589    while (__rt != nullptr)
2590    {
2591        if (value_comp()(__k, __rt->__value_))
2592        {
2593            __rt = static_cast<__node_pointer>(__rt->__left_);
2594        }
2595        else if (value_comp()(__rt->__value_, __k))
2596            __rt = static_cast<__node_pointer>(__rt->__right_);
2597        else
2598            return 1;
2599    }
2600    return 0;
2601}
2602
2603template <class _Tp, class _Compare, class _Allocator>
2604template <class _Key>
2605typename __tree<_Tp, _Compare, _Allocator>::size_type
2606__tree<_Tp, _Compare, _Allocator>::__count_multi(const _Key& __k) const
2607{
2608    __iter_pointer __result = __end_node();
2609    __node_pointer __rt = __root();
2610    while (__rt != nullptr)
2611    {
2612        if (value_comp()(__k, __rt->__value_))
2613        {
2614            __result = static_cast<__iter_pointer>(__rt);
2615            __rt = static_cast<__node_pointer>(__rt->__left_);
2616        }
2617        else if (value_comp()(__rt->__value_, __k))
2618            __rt = static_cast<__node_pointer>(__rt->__right_);
2619        else
2620            return _VSTD::distance(
2621                __lower_bound(__k, static_cast<__node_pointer>(__rt->__left_), static_cast<__iter_pointer>(__rt)),
2622                __upper_bound(__k, static_cast<__node_pointer>(__rt->__right_), __result)
2623            );
2624    }
2625    return 0;
2626}
2627
2628template <class _Tp, class _Compare, class _Allocator>
2629template <class _Key>
2630typename __tree<_Tp, _Compare, _Allocator>::iterator
2631__tree<_Tp, _Compare, _Allocator>::__lower_bound(const _Key& __v,
2632                                                 __node_pointer __root,
2633                                                 __iter_pointer __result)
2634{
2635    while (__root != nullptr)
2636    {
2637        if (!value_comp()(__root->__value_, __v))
2638        {
2639            __result = static_cast<__iter_pointer>(__root);
2640            __root = static_cast<__node_pointer>(__root->__left_);
2641        }
2642        else
2643            __root = static_cast<__node_pointer>(__root->__right_);
2644    }
2645    return iterator(__result);
2646}
2647
2648template <class _Tp, class _Compare, class _Allocator>
2649template <class _Key>
2650typename __tree<_Tp, _Compare, _Allocator>::const_iterator
2651__tree<_Tp, _Compare, _Allocator>::__lower_bound(const _Key& __v,
2652                                                 __node_pointer __root,
2653                                                 __iter_pointer __result) const
2654{
2655    while (__root != nullptr)
2656    {
2657        if (!value_comp()(__root->__value_, __v))
2658        {
2659            __result = static_cast<__iter_pointer>(__root);
2660            __root = static_cast<__node_pointer>(__root->__left_);
2661        }
2662        else
2663            __root = static_cast<__node_pointer>(__root->__right_);
2664    }
2665    return const_iterator(__result);
2666}
2667
2668template <class _Tp, class _Compare, class _Allocator>
2669template <class _Key>
2670typename __tree<_Tp, _Compare, _Allocator>::iterator
2671__tree<_Tp, _Compare, _Allocator>::__upper_bound(const _Key& __v,
2672                                                 __node_pointer __root,
2673                                                 __iter_pointer __result)
2674{
2675    while (__root != nullptr)
2676    {
2677        if (value_comp()(__v, __root->__value_))
2678        {
2679            __result = static_cast<__iter_pointer>(__root);
2680            __root = static_cast<__node_pointer>(__root->__left_);
2681        }
2682        else
2683            __root = static_cast<__node_pointer>(__root->__right_);
2684    }
2685    return iterator(__result);
2686}
2687
2688template <class _Tp, class _Compare, class _Allocator>
2689template <class _Key>
2690typename __tree<_Tp, _Compare, _Allocator>::const_iterator
2691__tree<_Tp, _Compare, _Allocator>::__upper_bound(const _Key& __v,
2692                                                 __node_pointer __root,
2693                                                 __iter_pointer __result) const
2694{
2695    while (__root != nullptr)
2696    {
2697        if (value_comp()(__v, __root->__value_))
2698        {
2699            __result = static_cast<__iter_pointer>(__root);
2700            __root = static_cast<__node_pointer>(__root->__left_);
2701        }
2702        else
2703            __root = static_cast<__node_pointer>(__root->__right_);
2704    }
2705    return const_iterator(__result);
2706}
2707
2708template <class _Tp, class _Compare, class _Allocator>
2709template <class _Key>
2710pair<typename __tree<_Tp, _Compare, _Allocator>::iterator,
2711     typename __tree<_Tp, _Compare, _Allocator>::iterator>
2712__tree<_Tp, _Compare, _Allocator>::__equal_range_unique(const _Key& __k)
2713{
2714    typedef pair<iterator, iterator> _Pp;
2715    __iter_pointer __result = __end_node();
2716    __node_pointer __rt = __root();
2717    while (__rt != nullptr)
2718    {
2719        if (value_comp()(__k, __rt->__value_))
2720        {
2721            __result = static_cast<__iter_pointer>(__rt);
2722            __rt = static_cast<__node_pointer>(__rt->__left_);
2723        }
2724        else if (value_comp()(__rt->__value_, __k))
2725            __rt = static_cast<__node_pointer>(__rt->__right_);
2726        else
2727            return _Pp(iterator(__rt),
2728                      iterator(
2729                          __rt->__right_ != nullptr ?
2730                              static_cast<__iter_pointer>(__tree_min(__rt->__right_))
2731                            : __result));
2732    }
2733    return _Pp(iterator(__result), iterator(__result));
2734}
2735
2736template <class _Tp, class _Compare, class _Allocator>
2737template <class _Key>
2738pair<typename __tree<_Tp, _Compare, _Allocator>::const_iterator,
2739     typename __tree<_Tp, _Compare, _Allocator>::const_iterator>
2740__tree<_Tp, _Compare, _Allocator>::__equal_range_unique(const _Key& __k) const
2741{
2742    typedef pair<const_iterator, const_iterator> _Pp;
2743    __iter_pointer __result = __end_node();
2744    __node_pointer __rt = __root();
2745    while (__rt != nullptr)
2746    {
2747        if (value_comp()(__k, __rt->__value_))
2748        {
2749            __result = static_cast<__iter_pointer>(__rt);
2750            __rt = static_cast<__node_pointer>(__rt->__left_);
2751        }
2752        else if (value_comp()(__rt->__value_, __k))
2753            __rt = static_cast<__node_pointer>(__rt->__right_);
2754        else
2755            return _Pp(const_iterator(__rt),
2756                      const_iterator(
2757                          __rt->__right_ != nullptr ?
2758                              static_cast<__iter_pointer>(__tree_min(__rt->__right_))
2759                            : __result));
2760    }
2761    return _Pp(const_iterator(__result), const_iterator(__result));
2762}
2763
2764template <class _Tp, class _Compare, class _Allocator>
2765template <class _Key>
2766pair<typename __tree<_Tp, _Compare, _Allocator>::iterator,
2767     typename __tree<_Tp, _Compare, _Allocator>::iterator>
2768__tree<_Tp, _Compare, _Allocator>::__equal_range_multi(const _Key& __k)
2769{
2770    typedef pair<iterator, iterator> _Pp;
2771    __iter_pointer __result = __end_node();
2772    __node_pointer __rt = __root();
2773    while (__rt != nullptr)
2774    {
2775        if (value_comp()(__k, __rt->__value_))
2776        {
2777            __result = static_cast<__iter_pointer>(__rt);
2778            __rt = static_cast<__node_pointer>(__rt->__left_);
2779        }
2780        else if (value_comp()(__rt->__value_, __k))
2781            __rt = static_cast<__node_pointer>(__rt->__right_);
2782        else
2783            return _Pp(__lower_bound(__k, static_cast<__node_pointer>(__rt->__left_), static_cast<__iter_pointer>(__rt)),
2784                      __upper_bound(__k, static_cast<__node_pointer>(__rt->__right_), __result));
2785    }
2786    return _Pp(iterator(__result), iterator(__result));
2787}
2788
2789template <class _Tp, class _Compare, class _Allocator>
2790template <class _Key>
2791pair<typename __tree<_Tp, _Compare, _Allocator>::const_iterator,
2792     typename __tree<_Tp, _Compare, _Allocator>::const_iterator>
2793__tree<_Tp, _Compare, _Allocator>::__equal_range_multi(const _Key& __k) const
2794{
2795    typedef pair<const_iterator, const_iterator> _Pp;
2796    __iter_pointer __result = __end_node();
2797    __node_pointer __rt = __root();
2798    while (__rt != nullptr)
2799    {
2800        if (value_comp()(__k, __rt->__value_))
2801        {
2802            __result = static_cast<__iter_pointer>(__rt);
2803            __rt = static_cast<__node_pointer>(__rt->__left_);
2804        }
2805        else if (value_comp()(__rt->__value_, __k))
2806            __rt = static_cast<__node_pointer>(__rt->__right_);
2807        else
2808            return _Pp(__lower_bound(__k, static_cast<__node_pointer>(__rt->__left_), static_cast<__iter_pointer>(__rt)),
2809                      __upper_bound(__k, static_cast<__node_pointer>(__rt->__right_), __result));
2810    }
2811    return _Pp(const_iterator(__result), const_iterator(__result));
2812}
2813
2814template <class _Tp, class _Compare, class _Allocator>
2815typename __tree<_Tp, _Compare, _Allocator>::__node_holder
2816__tree<_Tp, _Compare, _Allocator>::remove(const_iterator __p) _NOEXCEPT
2817{
2818    __node_pointer __np = __p.__get_np();
2819    if (__begin_node() == __p.__ptr_)
2820    {
2821        if (__np->__right_ != nullptr)
2822            __begin_node() = static_cast<__iter_pointer>(__np->__right_);
2823        else
2824            __begin_node() = static_cast<__iter_pointer>(__np->__parent_);
2825    }
2826    --size();
2827    __tree_remove(__end_node()->__left_,
2828                  static_cast<__node_base_pointer>(__np));
2829    return __node_holder(__np, _Dp(__node_alloc(), true));
2830}
2831
2832template <class _Tp, class _Compare, class _Allocator>
2833inline _LIBCPP_INLINE_VISIBILITY
2834void
2835swap(__tree<_Tp, _Compare, _Allocator>& __x,
2836     __tree<_Tp, _Compare, _Allocator>& __y)
2837    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
2838{
2839    __x.swap(__y);
2840}
2841
2842_LIBCPP_END_NAMESPACE_STD
2843
2844_LIBCPP_POP_MACROS
2845
2846#endif  // _LIBCPP___TREE
2847