1// Singly-linked list implementation -*- C++ -*-
2
3// Copyright (C) 2001-2018 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library.  This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
23// <http://www.gnu.org/licenses/>.
24
25/*
26 * Copyright (c) 1997
27 * Silicon Graphics Computer Systems, Inc.
28 *
29 * Permission to use, copy, modify, distribute and sell this software
30 * and its documentation for any purpose is hereby granted without fee,
31 * provided that the above copyright notice appear in all copies and
32 * that both that copyright notice and this permission notice appear
33 * in supporting documentation.  Silicon Graphics makes no
34 * representations about the suitability of this software for any
35 * purpose.  It is provided "as is" without express or implied warranty.
36 *
37 */
38
39/** @file ext/slist
40 *  This file is a GNU extension to the Standard C++ Library (possibly
41 *  containing extensions from the HP/SGI STL subset).
42 */
43
44#ifndef _SLIST
45#define _SLIST 1
46
47#include <algorithm>
48#include <bits/allocator.h>
49#include <bits/stl_construct.h>
50#include <bits/stl_uninitialized.h>
51#include <bits/concept_check.h>
52
53namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
54{
55_GLIBCXX_BEGIN_NAMESPACE_VERSION
56
57  using std::size_t;
58  using std::ptrdiff_t;
59  using std::_Construct;
60  using std::_Destroy;
61  using std::allocator;
62  using std::__true_type;
63  using std::__false_type;
64
65  struct _Slist_node_base
66  {
67    _Slist_node_base* _M_next;
68  };
69
70  inline _Slist_node_base*
71  __slist_make_link(_Slist_node_base* __prev_node,
72		    _Slist_node_base* __new_node)
73  {
74    __new_node->_M_next = __prev_node->_M_next;
75    __prev_node->_M_next = __new_node;
76    return __new_node;
77  }
78
79  inline _Slist_node_base*
80  __slist_previous(_Slist_node_base* __head,
81		   const _Slist_node_base* __node)
82  {
83    while (__head && __head->_M_next != __node)
84      __head = __head->_M_next;
85    return __head;
86  }
87
88  inline const _Slist_node_base*
89  __slist_previous(const _Slist_node_base* __head,
90		   const _Slist_node_base* __node)
91  {
92    while (__head && __head->_M_next != __node)
93      __head = __head->_M_next;
94    return __head;
95  }
96
97  inline void
98  __slist_splice_after(_Slist_node_base* __pos,
99		       _Slist_node_base* __before_first,
100		       _Slist_node_base* __before_last)
101  {
102    if (__pos != __before_first && __pos != __before_last)
103      {
104	_Slist_node_base* __first = __before_first->_M_next;
105	_Slist_node_base* __after = __pos->_M_next;
106	__before_first->_M_next = __before_last->_M_next;
107	__pos->_M_next = __first;
108	__before_last->_M_next = __after;
109      }
110  }
111
112  inline void
113  __slist_splice_after(_Slist_node_base* __pos, _Slist_node_base* __head)
114  {
115    _Slist_node_base* __before_last = __slist_previous(__head, 0);
116    if (__before_last != __head)
117      {
118	_Slist_node_base* __after = __pos->_M_next;
119	__pos->_M_next = __head->_M_next;
120	__head->_M_next = 0;
121	__before_last->_M_next = __after;
122      }
123  }
124
125  inline _Slist_node_base*
126  __slist_reverse(_Slist_node_base* __node)
127  {
128    _Slist_node_base* __result = __node;
129    __node = __node->_M_next;
130    __result->_M_next = 0;
131    while(__node)
132      {
133	_Slist_node_base* __next = __node->_M_next;
134	__node->_M_next = __result;
135	__result = __node;
136	__node = __next;
137      }
138    return __result;
139  }
140
141  inline size_t
142  __slist_size(_Slist_node_base* __node)
143  {
144    size_t __result = 0;
145    for (; __node != 0; __node = __node->_M_next)
146      ++__result;
147    return __result;
148  }
149
150  template <class _Tp>
151    struct _Slist_node : public _Slist_node_base
152    {
153      _Tp _M_data;
154    };
155
156  struct _Slist_iterator_base
157  {
158    typedef size_t                    size_type;
159    typedef ptrdiff_t                 difference_type;
160    typedef std::forward_iterator_tag iterator_category;
161
162    _Slist_node_base* _M_node;
163
164    _Slist_iterator_base(_Slist_node_base* __x)
165    : _M_node(__x) {}
166
167    void
168    _M_incr()
169    { _M_node = _M_node->_M_next; }
170
171    bool
172    operator==(const _Slist_iterator_base& __x) const
173    { return _M_node == __x._M_node; }
174
175    bool
176    operator!=(const _Slist_iterator_base& __x) const
177    { return _M_node != __x._M_node; }
178  };
179
180  template <class _Tp, class _Ref, class _Ptr>
181    struct _Slist_iterator : public _Slist_iterator_base
182    {
183      typedef _Slist_iterator<_Tp, _Tp&, _Tp*>             iterator;
184      typedef _Slist_iterator<_Tp, const _Tp&, const _Tp*> const_iterator;
185      typedef _Slist_iterator<_Tp, _Ref, _Ptr>             _Self;
186
187      typedef _Tp              value_type;
188      typedef _Ptr             pointer;
189      typedef _Ref             reference;
190      typedef _Slist_node<_Tp> _Node;
191
192      explicit
193      _Slist_iterator(_Node* __x)
194      : _Slist_iterator_base(__x) {}
195
196      _Slist_iterator()
197      : _Slist_iterator_base(0) {}
198
199      _Slist_iterator(const iterator& __x)
200      : _Slist_iterator_base(__x._M_node) {}
201
202      reference
203      operator*() const
204      { return ((_Node*) _M_node)->_M_data; }
205
206      pointer
207      operator->() const
208      { return &(operator*()); }
209
210      _Self&
211      operator++()
212      {
213	_M_incr();
214	return *this;
215      }
216
217      _Self
218      operator++(int)
219      {
220	_Self __tmp = *this;
221	_M_incr();
222	return __tmp;
223      }
224    };
225
226  template <class _Tp, class _Alloc>
227    struct _Slist_base
228    : public _Alloc::template rebind<_Slist_node<_Tp> >::other
229    {
230      typedef typename _Alloc::template rebind<_Slist_node<_Tp> >::other
231        _Node_alloc;
232      typedef _Alloc allocator_type;
233
234      allocator_type
235      get_allocator() const
236      { return *static_cast<const _Node_alloc*>(this); }
237
238      _Slist_base(const allocator_type& __a)
239      : _Node_alloc(__a)
240      { this->_M_head._M_next = 0; }
241
242      ~_Slist_base()
243      { _M_erase_after(&this->_M_head, 0); }
244
245    protected:
246      _Slist_node_base _M_head;
247
248      _Slist_node<_Tp>*
249      _M_get_node()
250      { return _Node_alloc::allocate(1); }
251
252      void
253      _M_put_node(_Slist_node<_Tp>* __p)
254      { _Node_alloc::deallocate(__p, 1); }
255
256    protected:
257      _Slist_node_base* _M_erase_after(_Slist_node_base* __pos)
258      {
259	_Slist_node<_Tp>* __next = (_Slist_node<_Tp>*) (__pos->_M_next);
260	_Slist_node_base* __next_next = __next->_M_next;
261	__pos->_M_next = __next_next;
262	get_allocator().destroy(&__next->_M_data);
263	_M_put_node(__next);
264	return __next_next;
265      }
266      _Slist_node_base* _M_erase_after(_Slist_node_base*, _Slist_node_base*);
267    };
268
269  template <class _Tp, class _Alloc>
270    _Slist_node_base*
271    _Slist_base<_Tp,_Alloc>::_M_erase_after(_Slist_node_base* __before_first,
272					    _Slist_node_base* __last_node)
273    {
274      _Slist_node<_Tp>* __cur = (_Slist_node<_Tp>*) (__before_first->_M_next);
275      while (__cur != __last_node)
276	{
277	  _Slist_node<_Tp>* __tmp = __cur;
278	  __cur = (_Slist_node<_Tp>*) __cur->_M_next;
279	  get_allocator().destroy(&__tmp->_M_data);
280	  _M_put_node(__tmp);
281	}
282      __before_first->_M_next = __last_node;
283      return __last_node;
284    }
285
286  /**
287   *  This is an SGI extension.
288   *  @ingroup SGIextensions
289   *  @doctodo
290   */
291  template <class _Tp, class _Alloc = allocator<_Tp> >
292    class slist : private _Slist_base<_Tp,_Alloc>
293    {
294      // concept requirements
295      __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
296
297    private:
298      typedef _Slist_base<_Tp,_Alloc> _Base;
299
300    public:
301      typedef _Tp               value_type;
302      typedef value_type*       pointer;
303      typedef const value_type* const_pointer;
304      typedef value_type&       reference;
305      typedef const value_type& const_reference;
306      typedef size_t            size_type;
307      typedef ptrdiff_t         difference_type;
308
309      typedef _Slist_iterator<_Tp, _Tp&, _Tp*>             iterator;
310      typedef _Slist_iterator<_Tp, const _Tp&, const _Tp*> const_iterator;
311
312      typedef typename _Base::allocator_type allocator_type;
313
314      allocator_type
315      get_allocator() const
316      { return _Base::get_allocator(); }
317
318    private:
319      typedef _Slist_node<_Tp>      _Node;
320      typedef _Slist_node_base      _Node_base;
321      typedef _Slist_iterator_base  _Iterator_base;
322
323      _Node*
324      _M_create_node(const value_type& __x)
325      {
326	_Node* __node = this->_M_get_node();
327	__try
328	  {
329	    get_allocator().construct(&__node->_M_data, __x);
330	    __node->_M_next = 0;
331	  }
332	__catch(...)
333	  {
334	    this->_M_put_node(__node);
335	    __throw_exception_again;
336	  }
337	return __node;
338      }
339
340      _Node*
341      _M_create_node()
342      {
343	_Node* __node = this->_M_get_node();
344	__try
345	  {
346	    get_allocator().construct(&__node->_M_data, value_type());
347	    __node->_M_next = 0;
348	  }
349	__catch(...)
350	  {
351	    this->_M_put_node(__node);
352	    __throw_exception_again;
353	  }
354	return __node;
355      }
356
357    public:
358      explicit
359      slist(const allocator_type& __a = allocator_type())
360      : _Base(__a) {}
361
362      slist(size_type __n, const value_type& __x,
363	    const allocator_type& __a =  allocator_type())
364      : _Base(__a)
365      { _M_insert_after_fill(&this->_M_head, __n, __x); }
366
367      explicit
368      slist(size_type __n)
369      : _Base(allocator_type())
370      { _M_insert_after_fill(&this->_M_head, __n, value_type()); }
371
372      // We don't need any dispatching tricks here, because
373      // _M_insert_after_range already does them.
374      template <class _InputIterator>
375        slist(_InputIterator __first, _InputIterator __last,
376	      const allocator_type& __a =  allocator_type())
377	: _Base(__a)
378        { _M_insert_after_range(&this->_M_head, __first, __last); }
379
380      slist(const slist& __x)
381      : _Base(__x.get_allocator())
382      { _M_insert_after_range(&this->_M_head, __x.begin(), __x.end()); }
383
384      slist&
385      operator= (const slist& __x);
386
387      ~slist() {}
388
389    public:
390      // assign(), a generalized assignment member function.  Two
391      // versions: one that takes a count, and one that takes a range.
392      // The range version is a member template, so we dispatch on whether
393      // or not the type is an integer.
394
395      void
396      assign(size_type __n, const _Tp& __val)
397      { _M_fill_assign(__n, __val); }
398
399      void
400      _M_fill_assign(size_type __n, const _Tp& __val);
401
402      template <class _InputIterator>
403        void
404        assign(_InputIterator __first, _InputIterator __last)
405        {
406	  typedef typename std::__is_integer<_InputIterator>::__type _Integral;
407	  _M_assign_dispatch(__first, __last, _Integral());
408	}
409
410      template <class _Integer>
411      void
412      _M_assign_dispatch(_Integer __n, _Integer __val, __true_type)
413      { _M_fill_assign((size_type) __n, (_Tp) __val); }
414
415      template <class _InputIterator>
416      void
417      _M_assign_dispatch(_InputIterator __first, _InputIterator __last,
418			 __false_type);
419
420    public:
421
422      iterator
423      begin()
424      { return iterator((_Node*)this->_M_head._M_next); }
425
426      const_iterator
427      begin() const
428      { return const_iterator((_Node*)this->_M_head._M_next);}
429
430      iterator
431      end()
432      { return iterator(0); }
433
434      const_iterator
435      end() const
436      { return const_iterator(0); }
437
438      // Experimental new feature: before_begin() returns a
439      // non-dereferenceable iterator that, when incremented, yields
440      // begin().  This iterator may be used as the argument to
441      // insert_after, erase_after, etc.  Note that even for an empty
442      // slist, before_begin() is not the same iterator as end().  It
443      // is always necessary to increment before_begin() at least once to
444      // obtain end().
445      iterator
446      before_begin()
447      { return iterator((_Node*) &this->_M_head); }
448
449      const_iterator
450      before_begin() const
451      { return const_iterator((_Node*) &this->_M_head); }
452
453      size_type
454      size() const
455      { return __slist_size(this->_M_head._M_next); }
456
457      size_type
458      max_size() const
459      { return size_type(-1); }
460
461      bool
462      empty() const
463      { return this->_M_head._M_next == 0; }
464
465      void
466      swap(slist& __x)
467      { std::swap(this->_M_head._M_next, __x._M_head._M_next); }
468
469    public:
470
471      reference
472      front()
473      { return ((_Node*) this->_M_head._M_next)->_M_data; }
474
475      const_reference
476      front() const
477      { return ((_Node*) this->_M_head._M_next)->_M_data; }
478
479      void
480      push_front(const value_type& __x)
481      { __slist_make_link(&this->_M_head, _M_create_node(__x)); }
482
483      void
484      push_front()
485      { __slist_make_link(&this->_M_head, _M_create_node()); }
486
487      void
488      pop_front()
489      {
490	_Node* __node = (_Node*) this->_M_head._M_next;
491	this->_M_head._M_next = __node->_M_next;
492	get_allocator().destroy(&__node->_M_data);
493	this->_M_put_node(__node);
494      }
495
496      iterator
497      previous(const_iterator __pos)
498      { return iterator((_Node*) __slist_previous(&this->_M_head,
499						  __pos._M_node)); }
500
501      const_iterator
502      previous(const_iterator __pos) const
503      { return const_iterator((_Node*) __slist_previous(&this->_M_head,
504							__pos._M_node)); }
505
506    private:
507      _Node*
508      _M_insert_after(_Node_base* __pos, const value_type& __x)
509      { return (_Node*) (__slist_make_link(__pos, _M_create_node(__x))); }
510
511      _Node*
512      _M_insert_after(_Node_base* __pos)
513      { return (_Node*) (__slist_make_link(__pos, _M_create_node())); }
514
515      void
516      _M_insert_after_fill(_Node_base* __pos,
517			   size_type __n, const value_type& __x)
518      {
519	for (size_type __i = 0; __i < __n; ++__i)
520	  __pos = __slist_make_link(__pos, _M_create_node(__x));
521      }
522
523      // Check whether it's an integral type.  If so, it's not an iterator.
524      template <class _InIterator>
525        void
526        _M_insert_after_range(_Node_base* __pos,
527			      _InIterator __first, _InIterator __last)
528        {
529	  typedef typename std::__is_integer<_InIterator>::__type _Integral;
530	  _M_insert_after_range(__pos, __first, __last, _Integral());
531	}
532
533      template <class _Integer>
534        void
535        _M_insert_after_range(_Node_base* __pos, _Integer __n, _Integer __x,
536			      __true_type)
537        { _M_insert_after_fill(__pos, __n, __x); }
538
539      template <class _InIterator>
540        void
541        _M_insert_after_range(_Node_base* __pos,
542			      _InIterator __first, _InIterator __last,
543			      __false_type)
544        {
545	  while (__first != __last)
546	    {
547	      __pos = __slist_make_link(__pos, _M_create_node(*__first));
548	      ++__first;
549	    }
550	}
551
552    public:
553      iterator
554      insert_after(iterator __pos, const value_type& __x)
555      { return iterator(_M_insert_after(__pos._M_node, __x)); }
556
557      iterator
558      insert_after(iterator __pos)
559      { return insert_after(__pos, value_type()); }
560
561      void
562      insert_after(iterator __pos, size_type __n, const value_type& __x)
563      { _M_insert_after_fill(__pos._M_node, __n, __x); }
564
565      // We don't need any dispatching tricks here, because
566      // _M_insert_after_range already does them.
567      template <class _InIterator>
568        void
569        insert_after(iterator __pos, _InIterator __first, _InIterator __last)
570        { _M_insert_after_range(__pos._M_node, __first, __last); }
571
572      iterator
573      insert(iterator __pos, const value_type& __x)
574      { return iterator(_M_insert_after(__slist_previous(&this->_M_head,
575							 __pos._M_node),
576					__x)); }
577
578      iterator
579      insert(iterator __pos)
580      { return iterator(_M_insert_after(__slist_previous(&this->_M_head,
581							 __pos._M_node),
582					value_type())); }
583
584      void
585      insert(iterator __pos, size_type __n, const value_type& __x)
586      { _M_insert_after_fill(__slist_previous(&this->_M_head, __pos._M_node),
587			     __n, __x); }
588
589      // We don't need any dispatching tricks here, because
590      // _M_insert_after_range already does them.
591      template <class _InIterator>
592        void
593        insert(iterator __pos, _InIterator __first, _InIterator __last)
594        { _M_insert_after_range(__slist_previous(&this->_M_head, __pos._M_node),
595				__first, __last); }
596
597    public:
598      iterator
599      erase_after(iterator __pos)
600      { return iterator((_Node*) this->_M_erase_after(__pos._M_node)); }
601
602      iterator
603      erase_after(iterator __before_first, iterator __last)
604      {
605	return iterator((_Node*) this->_M_erase_after(__before_first._M_node,
606						      __last._M_node));
607      }
608
609      iterator
610      erase(iterator __pos)
611      {
612	return iterator((_Node*) this->_M_erase_after
613			(__slist_previous(&this->_M_head, __pos._M_node)));
614      }
615
616      iterator
617      erase(iterator __first, iterator __last)
618      {
619	return iterator((_Node*) this->_M_erase_after
620			(__slist_previous(&this->_M_head, __first._M_node),
621			 __last._M_node));
622      }
623
624      void
625      resize(size_type new_size, const _Tp& __x);
626
627      void
628      resize(size_type new_size)
629      { resize(new_size, _Tp()); }
630
631      void
632      clear()
633      { this->_M_erase_after(&this->_M_head, 0); }
634
635    public:
636      // Moves the range [__before_first + 1, __before_last + 1) to *this,
637      //  inserting it immediately after __pos.  This is constant time.
638      void
639      splice_after(iterator __pos,
640		   iterator __before_first, iterator __before_last)
641      {
642	if (__before_first != __before_last)
643	  __slist_splice_after(__pos._M_node, __before_first._M_node,
644			       __before_last._M_node);
645      }
646
647      // Moves the element that follows __prev to *this, inserting it
648      // immediately after __pos.  This is constant time.
649      void
650      splice_after(iterator __pos, iterator __prev)
651      { __slist_splice_after(__pos._M_node,
652			     __prev._M_node, __prev._M_node->_M_next); }
653
654      // Removes all of the elements from the list __x to *this, inserting
655      // them immediately after __pos.  __x must not be *this.  Complexity:
656      // linear in __x.size().
657      void
658      splice_after(iterator __pos, slist& __x)
659      { __slist_splice_after(__pos._M_node, &__x._M_head); }
660
661      // Linear in distance(begin(), __pos), and linear in __x.size().
662      void
663      splice(iterator __pos, slist& __x)
664      {
665	if (__x._M_head._M_next)
666	  __slist_splice_after(__slist_previous(&this->_M_head, __pos._M_node),
667			       &__x._M_head,
668			       __slist_previous(&__x._M_head, 0)); }
669
670      // Linear in distance(begin(), __pos), and in distance(__x.begin(), __i).
671      void
672      splice(iterator __pos, slist& __x, iterator __i)
673      { __slist_splice_after(__slist_previous(&this->_M_head, __pos._M_node),
674			     __slist_previous(&__x._M_head, __i._M_node),
675			     __i._M_node); }
676
677      // Linear in distance(begin(), __pos), in distance(__x.begin(), __first),
678      // and in distance(__first, __last).
679      void
680      splice(iterator __pos, slist& __x, iterator __first, iterator __last)
681      {
682	if (__first != __last)
683	  __slist_splice_after(__slist_previous(&this->_M_head, __pos._M_node),
684			       __slist_previous(&__x._M_head, __first._M_node),
685			       __slist_previous(__first._M_node,
686						__last._M_node));
687      }
688
689    public:
690      void
691      reverse()
692      {
693	if (this->_M_head._M_next)
694	  this->_M_head._M_next = __slist_reverse(this->_M_head._M_next);
695      }
696
697      void
698      remove(const _Tp& __val);
699
700      void
701      unique();
702
703      void
704      merge(slist& __x);
705
706      void
707      sort();
708
709      template <class _Predicate>
710        void
711        remove_if(_Predicate __pred);
712
713      template <class _BinaryPredicate>
714        void
715        unique(_BinaryPredicate __pred);
716
717      template <class _StrictWeakOrdering>
718        void
719        merge(slist&, _StrictWeakOrdering);
720
721      template <class _StrictWeakOrdering>
722        void
723        sort(_StrictWeakOrdering __comp);
724    };
725
726  template <class _Tp, class _Alloc>
727    slist<_Tp, _Alloc>&
728    slist<_Tp, _Alloc>::operator=(const slist<_Tp, _Alloc>& __x)
729    {
730      if (&__x != this)
731	{
732	  _Node_base* __p1 = &this->_M_head;
733	  _Node* __n1 = (_Node*) this->_M_head._M_next;
734	  const _Node* __n2 = (const _Node*) __x._M_head._M_next;
735	  while (__n1 && __n2)
736	    {
737	      __n1->_M_data = __n2->_M_data;
738	      __p1 = __n1;
739	      __n1 = (_Node*) __n1->_M_next;
740	      __n2 = (const _Node*) __n2->_M_next;
741	    }
742	  if (__n2 == 0)
743	    this->_M_erase_after(__p1, 0);
744	  else
745	    _M_insert_after_range(__p1, const_iterator((_Node*)__n2),
746                                  const_iterator(0));
747	}
748      return *this;
749    }
750
751  template <class _Tp, class _Alloc>
752    void
753    slist<_Tp, _Alloc>::_M_fill_assign(size_type __n, const _Tp& __val)
754    {
755      _Node_base* __prev = &this->_M_head;
756      _Node* __node = (_Node*) this->_M_head._M_next;
757      for (; __node != 0 && __n > 0; --__n)
758	{
759	  __node->_M_data = __val;
760	  __prev = __node;
761	  __node = (_Node*) __node->_M_next;
762	}
763      if (__n > 0)
764	_M_insert_after_fill(__prev, __n, __val);
765      else
766	this->_M_erase_after(__prev, 0);
767    }
768
769  template <class _Tp, class _Alloc>
770    template <class _InputIterator>
771      void
772      slist<_Tp, _Alloc>::_M_assign_dispatch(_InputIterator __first,
773					     _InputIterator __last,
774					     __false_type)
775      {
776	_Node_base* __prev = &this->_M_head;
777	_Node* __node = (_Node*) this->_M_head._M_next;
778	while (__node != 0 && __first != __last)
779	  {
780	    __node->_M_data = *__first;
781	    __prev = __node;
782	    __node = (_Node*) __node->_M_next;
783	    ++__first;
784	  }
785	if (__first != __last)
786	  _M_insert_after_range(__prev, __first, __last);
787	else
788	  this->_M_erase_after(__prev, 0);
789      }
790
791  template <class _Tp, class _Alloc>
792    inline bool
793    operator==(const slist<_Tp, _Alloc>& _SL1, const slist<_Tp, _Alloc>& _SL2)
794    {
795      typedef typename slist<_Tp,_Alloc>::const_iterator const_iterator;
796      const_iterator __end1 = _SL1.end();
797      const_iterator __end2 = _SL2.end();
798
799      const_iterator __i1 = _SL1.begin();
800      const_iterator __i2 = _SL2.begin();
801      while (__i1 != __end1 && __i2 != __end2 && *__i1 == *__i2)
802	{
803	  ++__i1;
804	  ++__i2;
805	}
806      return __i1 == __end1 && __i2 == __end2;
807    }
808
809
810  template <class _Tp, class _Alloc>
811    inline bool
812    operator<(const slist<_Tp, _Alloc>& _SL1, const slist<_Tp, _Alloc>& _SL2)
813    { return std::lexicographical_compare(_SL1.begin(), _SL1.end(),
814					  _SL2.begin(), _SL2.end()); }
815
816  template <class _Tp, class _Alloc>
817    inline bool
818    operator!=(const slist<_Tp, _Alloc>& _SL1, const slist<_Tp, _Alloc>& _SL2)
819    { return !(_SL1 == _SL2); }
820
821  template <class _Tp, class _Alloc>
822    inline bool
823    operator>(const slist<_Tp, _Alloc>& _SL1, const slist<_Tp, _Alloc>& _SL2)
824    { return _SL2 < _SL1; }
825
826  template <class _Tp, class _Alloc>
827    inline bool
828    operator<=(const slist<_Tp, _Alloc>& _SL1, const slist<_Tp, _Alloc>& _SL2)
829    { return !(_SL2 < _SL1); }
830
831  template <class _Tp, class _Alloc>
832    inline bool
833    operator>=(const slist<_Tp, _Alloc>& _SL1, const slist<_Tp, _Alloc>& _SL2)
834    { return !(_SL1 < _SL2); }
835
836  template <class _Tp, class _Alloc>
837    inline void
838    swap(slist<_Tp, _Alloc>& __x, slist<_Tp, _Alloc>& __y)
839    { __x.swap(__y); }
840
841  template <class _Tp, class _Alloc>
842    void
843    slist<_Tp, _Alloc>::resize(size_type __len, const _Tp& __x)
844    {
845      _Node_base* __cur = &this->_M_head;
846      while (__cur->_M_next != 0 && __len > 0)
847	{
848	  --__len;
849	  __cur = __cur->_M_next;
850	}
851      if (__cur->_M_next)
852	this->_M_erase_after(__cur, 0);
853      else
854	_M_insert_after_fill(__cur, __len, __x);
855    }
856
857  template <class _Tp, class _Alloc>
858    void
859    slist<_Tp, _Alloc>::remove(const _Tp& __val)
860    {
861      _Node_base* __cur = &this->_M_head;
862      while (__cur && __cur->_M_next)
863	{
864	  if (((_Node*) __cur->_M_next)->_M_data == __val)
865	    this->_M_erase_after(__cur);
866	  else
867	    __cur = __cur->_M_next;
868	}
869    }
870
871  template <class _Tp, class _Alloc>
872    void
873    slist<_Tp, _Alloc>::unique()
874    {
875      _Node_base* __cur = this->_M_head._M_next;
876      if (__cur)
877	{
878	  while (__cur->_M_next)
879	    {
880	      if (((_Node*)__cur)->_M_data
881		  == ((_Node*)(__cur->_M_next))->_M_data)
882		this->_M_erase_after(__cur);
883	      else
884		__cur = __cur->_M_next;
885	    }
886	}
887    }
888
889  template <class _Tp, class _Alloc>
890    void
891    slist<_Tp, _Alloc>::merge(slist<_Tp, _Alloc>& __x)
892    {
893      _Node_base* __n1 = &this->_M_head;
894      while (__n1->_M_next && __x._M_head._M_next)
895	{
896	  if (((_Node*) __x._M_head._M_next)->_M_data
897	      < ((_Node*) __n1->_M_next)->_M_data)
898	    __slist_splice_after(__n1, &__x._M_head, __x._M_head._M_next);
899	  __n1 = __n1->_M_next;
900	}
901      if (__x._M_head._M_next)
902	{
903	  __n1->_M_next = __x._M_head._M_next;
904	  __x._M_head._M_next = 0;
905	}
906    }
907
908  template <class _Tp, class _Alloc>
909    void
910    slist<_Tp, _Alloc>::sort()
911    {
912      if (this->_M_head._M_next && this->_M_head._M_next->_M_next)
913	{
914	  slist __carry;
915	  slist __counter[64];
916	  int __fill = 0;
917	  while (!empty())
918	    {
919	      __slist_splice_after(&__carry._M_head,
920				   &this->_M_head, this->_M_head._M_next);
921	      int __i = 0;
922	      while (__i < __fill && !__counter[__i].empty())
923		{
924		  __counter[__i].merge(__carry);
925		  __carry.swap(__counter[__i]);
926		  ++__i;
927		}
928	      __carry.swap(__counter[__i]);
929	      if (__i == __fill)
930		++__fill;
931	    }
932
933	  for (int __i = 1; __i < __fill; ++__i)
934	    __counter[__i].merge(__counter[__i-1]);
935	  this->swap(__counter[__fill-1]);
936	}
937    }
938
939  template <class _Tp, class _Alloc>
940    template <class _Predicate>
941      void slist<_Tp, _Alloc>::remove_if(_Predicate __pred)
942      {
943	_Node_base* __cur = &this->_M_head;
944	while (__cur->_M_next)
945	  {
946	    if (__pred(((_Node*) __cur->_M_next)->_M_data))
947	      this->_M_erase_after(__cur);
948	    else
949	      __cur = __cur->_M_next;
950	  }
951      }
952
953  template <class _Tp, class _Alloc>
954    template <class _BinaryPredicate>
955      void
956      slist<_Tp, _Alloc>::unique(_BinaryPredicate __pred)
957      {
958	_Node* __cur = (_Node*) this->_M_head._M_next;
959	if (__cur)
960	  {
961	    while (__cur->_M_next)
962	      {
963		if (__pred(((_Node*)__cur)->_M_data,
964			   ((_Node*)(__cur->_M_next))->_M_data))
965		  this->_M_erase_after(__cur);
966		else
967		  __cur = (_Node*) __cur->_M_next;
968	      }
969	  }
970      }
971
972  template <class _Tp, class _Alloc>
973    template <class _StrictWeakOrdering>
974      void
975      slist<_Tp, _Alloc>::merge(slist<_Tp, _Alloc>& __x,
976			       _StrictWeakOrdering __comp)
977      {
978	_Node_base* __n1 = &this->_M_head;
979	while (__n1->_M_next && __x._M_head._M_next)
980	  {
981	    if (__comp(((_Node*) __x._M_head._M_next)->_M_data,
982		       ((_Node*) __n1->_M_next)->_M_data))
983	      __slist_splice_after(__n1, &__x._M_head, __x._M_head._M_next);
984	    __n1 = __n1->_M_next;
985	  }
986	if (__x._M_head._M_next)
987	  {
988	    __n1->_M_next = __x._M_head._M_next;
989	    __x._M_head._M_next = 0;
990	  }
991      }
992
993  template <class _Tp, class _Alloc>
994    template <class _StrictWeakOrdering>
995      void
996      slist<_Tp, _Alloc>::sort(_StrictWeakOrdering __comp)
997      {
998	if (this->_M_head._M_next && this->_M_head._M_next->_M_next)
999	  {
1000	    slist __carry;
1001	    slist __counter[64];
1002	    int __fill = 0;
1003	    while (!empty())
1004	      {
1005		__slist_splice_after(&__carry._M_head,
1006				     &this->_M_head, this->_M_head._M_next);
1007		int __i = 0;
1008		while (__i < __fill && !__counter[__i].empty())
1009		  {
1010		    __counter[__i].merge(__carry, __comp);
1011		    __carry.swap(__counter[__i]);
1012		    ++__i;
1013		  }
1014		__carry.swap(__counter[__i]);
1015		if (__i == __fill)
1016		  ++__fill;
1017	      }
1018
1019	    for (int __i = 1; __i < __fill; ++__i)
1020	      __counter[__i].merge(__counter[__i-1], __comp);
1021	    this->swap(__counter[__fill-1]);
1022	  }
1023      }
1024
1025_GLIBCXX_END_NAMESPACE_VERSION
1026} // namespace
1027
1028namespace std _GLIBCXX_VISIBILITY(default)
1029{
1030_GLIBCXX_BEGIN_NAMESPACE_VERSION
1031
1032  // Specialization of insert_iterator so that insertions will be constant
1033  // time rather than linear time.
1034  template <class _Tp, class _Alloc>
1035    class insert_iterator<__gnu_cxx::slist<_Tp, _Alloc> >
1036    {
1037    protected:
1038      typedef __gnu_cxx::slist<_Tp, _Alloc> _Container;
1039      _Container* container;
1040      typename _Container::iterator iter;
1041
1042    public:
1043      typedef _Container          container_type;
1044      typedef output_iterator_tag iterator_category;
1045      typedef void                value_type;
1046      typedef void                difference_type;
1047      typedef void                pointer;
1048      typedef void                reference;
1049
1050      insert_iterator(_Container& __x, typename _Container::iterator __i)
1051      : container(&__x)
1052      {
1053	if (__i == __x.begin())
1054	  iter = __x.before_begin();
1055	else
1056	  iter = __x.previous(__i);
1057      }
1058
1059      insert_iterator<_Container>&
1060      operator=(const typename _Container::value_type& __value)
1061      {
1062	iter = container->insert_after(iter, __value);
1063	return *this;
1064      }
1065
1066      insert_iterator<_Container>&
1067      operator*()
1068      { return *this; }
1069
1070      insert_iterator<_Container>&
1071      operator++()
1072      { return *this; }
1073
1074      insert_iterator<_Container>&
1075      operator++(int)
1076      { return *this; }
1077    };
1078
1079_GLIBCXX_END_NAMESPACE_VERSION
1080} // namespace
1081
1082#endif
1083