libstdc++-v3/include/bits/stl_multiset.h

   1 // Multiset implementation -*- C++ -*-
   2
   3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
   4 // Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 2, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING.  If not, write to the Free
  19 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  20 // USA.
  21
  22 // As a special exception, you may use this file as part of a free software
  23 // library without restriction.  Specifically, if other files instantiate
  24 // templates or use macros or inline functions from this file, or you compile
  25 // this file and link it with other files to produce an executable, this
  26 // file does not by itself cause the resulting executable to be covered by
  27 // the GNU General Public License.  This exception does not however
  28 // invalidate any other reasons why the executable file might be covered by
  29 // the GNU General Public License.
  30
  31 /*
  32  *
  33  * Copyright (c) 1994
  34  * Hewlett-Packard Company
  35  *
  36  * Permission to use, copy, modify, distribute and sell this software
  37  * and its documentation for any purpose is hereby granted without fee,
  38  * provided that the above copyright notice appear in all copies and
  39  * that both that copyright notice and this permission notice appear
  40  * in supporting documentation.  Hewlett-Packard Company makes no
  41  * representations about the suitability of this software for any
  42  * purpose.  It is provided "as is" without express or implied warranty.
  43  *
  44  *
  45  * Copyright (c) 1996
  46  * Silicon Graphics Computer Systems, Inc.
  47  *
  48  * Permission to use, copy, modify, distribute and sell this software
  49  * and its documentation for any purpose is hereby granted without fee,
  50  * provided that the above copyright notice appear in all copies and
  51  * that both that copyright notice and this permission notice appear
  52  * in supporting documentation.  Silicon Graphics makes no
  53  * representations about the suitability of this software for any
  54  * purpose.  It is provided "as is" without express or implied warranty.
  55  */
  56
  57 /** @file stl_multiset.h
  58  *  This is an internal header file, included by other library headers.
  59  *  You should not attempt to use it directly.
  60  */
  61
  62 #ifndef _STL_MULTISET_H
  63 #define _STL_MULTISET_H 1
  64
  65 #include <bits/concept_check.h>
  66
  67 _GLIBCXX_BEGIN_NESTED_NAMESPACE(std, _GLIBCXX_STD_D)
  68
  69   /**
  70    *  @brief A standard container made up of elements, which can be retrieved
  71    *  in logarithmic time.
  72    *
  73    *  @ingroup Containers
  74    *  @ingroup Assoc_containers
  75    *
  76    *  Meets the requirements of a <a href="tables.html#65">container</a>, a
  77    *  <a href="tables.html#66">reversible container</a>, and an
  78    *  <a href="tables.html#69">associative container</a> (using equivalent
  79    *  keys).  For a @c multiset<Key> the key_type and value_type are Key.
  80    *
  81    *  Multisets support bidirectional iterators.
  82    *
  83    *  @if maint
  84    *  The private tree data is declared exactly the same way for set and
  85    *  multiset; the distinction is made entirely in how the tree functions are
  86    *  called (*_unique versus *_equal, same as the standard).
  87    *  @endif
  88   */
  89   template <typename _Key, typename _Compare = std::less<_Key>,
  90             typename _Alloc = std::allocator<_Key> >
  91     class multiset
  92     {
  93       // concept requirements
  94       typedef typename _Alloc::value_type                   _Alloc_value_type;
  95       __glibcxx_class_requires(_Key, _SGIAssignableConcept)
  96       __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
  97                                 _BinaryFunctionConcept)
  98       __glibcxx_class_requires2(_Key, _Alloc_value_type, _SameTypeConcept)
  99
 100     public:
 101       // typedefs:
 102       typedef _Key     key_type;
 103       typedef _Key     value_type;
 104       typedef _Compare key_compare;
 105       typedef _Compare value_compare;
 106       typedef _Alloc   allocator_type;
 107
 108     private:
 109       /// @if maint  This turns a red-black tree into a [multi]set.  @endif
 110       typedef typename _Alloc::template rebind<_Key>::other _Key_alloc_type;
 111
 112       typedef _Rb_tree<key_type, value_type, _Identity<value_type>,
 113                        key_compare, _Key_alloc_type> _Rep_type;
 114       /// @if maint  The actual tree structure.  @endif
 115       _Rep_type _M_t;
 116
 117     public:
 118       typedef typename _Key_alloc_type::pointer             pointer;
 119       typedef typename _Key_alloc_type::const_pointer       const_pointer;
 120       typedef typename _Key_alloc_type::reference           reference;
 121       typedef typename _Key_alloc_type::const_reference     const_reference;
 122       // _GLIBCXX_RESOLVE_LIB_DEFECTS
 123       // DR 103. set::iterator is required to be modifiable,
 124       // but this allows modification of keys.
 125       typedef typename _Rep_type::const_iterator            iterator;
 126       typedef typename _Rep_type::const_iterator            const_iterator;
 127       typedef typename _Rep_type::const_reverse_iterator    reverse_iterator;
 128       typedef typename _Rep_type::const_reverse_iterator    const_reverse_iterator;
 129       typedef typename _Rep_type::size_type                 size_type;
 130       typedef typename _Rep_type::difference_type           difference_type;
 131
 132       // allocation/deallocation
 133       /**
 134        *  @brief  Default constructor creates no elements.
 135        */
 136       multiset()
 137       : _M_t() { }
 138
 139       /**
 140        *  @brief  Creates a %multiset with no elements.
 141        *  @param  comp  Comparator to use.
 142        *  @param  a  An allocator object.
 143        */
 144       explicit
 145       multiset(const _Compare& __comp,
 146                const allocator_type& __a = allocator_type())
 147       : _M_t(__comp, __a) { }
 148
 149       /**
 150        *  @brief  Builds a %multiset from a range.
 151        *  @param  first  An input iterator.
 152        *  @param  last  An input iterator.
 153        *
 154        *  Create a %multiset consisting of copies of the elements from
 155        *  [first,last).  This is linear in N if the range is already sorted,
 156        *  and NlogN otherwise (where N is distance(first,last)).
 157        */
 158       template<typename _InputIterator>
 159         multiset(_InputIterator __first, _InputIterator __last)
 160         : _M_t()
 161         { _M_t._M_insert_equal(__first, __last); }
 162
 163       /**
 164        *  @brief  Builds a %multiset from a range.
 165        *  @param  first  An input iterator.
 166        *  @param  last  An input iterator.
 167        *  @param  comp  A comparison functor.
 168        *  @param  a  An allocator object.
 169        *
 170        *  Create a %multiset consisting of copies of the elements from
 171        *  [first,last).  This is linear in N if the range is already sorted,
 172        *  and NlogN otherwise (where N is distance(first,last)).
 173        */
 174       template<typename _InputIterator>
 175         multiset(_InputIterator __first, _InputIterator __last,
 176                  const _Compare& __comp,
 177                  const allocator_type& __a = allocator_type())
 178         : _M_t(__comp, __a)
 179         { _M_t._M_insert_equal(__first, __last); }
 180
 181       /**
 182        *  @brief  %Multiset copy constructor.
 183        *  @param  x  A %multiset of identical element and allocator types.
 184        *
 185        *  The newly-created %multiset uses a copy of the allocation object used
 186        *  by @a x.
 187        */
 188       multiset(const multiset& __x)
 189       : _M_t(__x._M_t) { }
 190
 191 #ifdef __GXX_EXPERIMENTAL_CXX0X__
 192      /**
 193        *  @brief  %Multiset move constructor.
 194        *  @param  x  A %multiset of identical element and allocator types.
 195        *
 196        *  The newly-created %multiset contains the exact contents of @a x.
 197        *  The contents of @a x are a valid, but unspecified %multiset.
 198        */
 199       multiset(multiset&& __x)
 200       : _M_t(__x._M_t.key_comp(),
 201              __x._M_t._M_get_Node_allocator())
 202       { this->swap(__x); }
 203 #endif
 204
 205       /**
 206        *  @brief  %Multiset assignment operator.
 207        *  @param  x  A %multiset of identical element and allocator types.
 208        *
 209        *  All the elements of @a x are copied, but unlike the copy constructor,
 210        *  the allocator object is not copied.
 211        */
 212       multiset&
 213       operator=(const multiset& __x)
 214       {
 215         _M_t = __x._M_t;
 216         return *this;
 217       }
 218
 219 #ifdef __GXX_EXPERIMENTAL_CXX0X__
 220       /**
 221        *  @brief  %Multiset move assignment operator.
 222        *  @param  x  A %multiset of identical element and allocator types.
 223        *
 224        *  The contents of @a x are moved into this %multiset (without copying).
 225        *  @a x is a valid, but unspecified %multiset.
 226        */
 227       multiset&
 228       operator=(multiset&& __x)
 229       {
 230         this->swap(__x);
 231         return *this;
 232       }
 233 #endif
 234
 235       // accessors:
 236
 237       ///  Returns the comparison object.
 238       key_compare
 239       key_comp() const
 240       { return _M_t.key_comp(); }
 241       ///  Returns the comparison object.
 242       value_compare
 243       value_comp() const
 244       { return _M_t.key_comp(); }
 245       ///  Returns the memory allocation object.
 246       allocator_type
 247       get_allocator() const
 248       { return _M_t.get_allocator(); }
 249
 250       /**
 251        *  Returns a read/write iterator that points to the first element in the
 252        *  %multiset.  Iteration is done in ascending order according to the
 253        *  keys.
 254        */
 255       iterator
 256       begin() const
 257       { return _M_t.begin(); }
 258
 259       /**
 260        *  Returns a read/write iterator that points one past the last element in
 261        *  the %multiset.  Iteration is done in ascending order according to the
 262        *  keys.
 263        */
 264       iterator
 265       end() const
 266       { return _M_t.end(); }
 267
 268       /**
 269        *  Returns a read/write reverse iterator that points to the last element
 270        *  in the %multiset.  Iteration is done in descending order according to
 271        *  the keys.
 272        */
 273       reverse_iterator
 274       rbegin() const
 275       { return _M_t.rbegin(); }
 276
 277       /**
 278        *  Returns a read/write reverse iterator that points to the last element
 279        *  in the %multiset.  Iteration is done in descending order according to
 280        *  the keys.
 281        */
 282       reverse_iterator
 283       rend() const
 284       { return _M_t.rend(); }
 285
 286       ///  Returns true if the %set is empty.
 287       bool
 288       empty() const
 289       { return _M_t.empty(); }
 290
 291       ///  Returns the size of the %set.
 292       size_type
 293       size() const
 294       { return _M_t.size(); }
 295
 296       ///  Returns the maximum size of the %set.
 297       size_type
 298       max_size() const
 299       { return _M_t.max_size(); }
 300
 301       /**
 302        *  @brief  Swaps data with another %multiset.
 303        *  @param  x  A %multiset of the same element and allocator types.
 304        *
 305        *  This exchanges the elements between two multisets in constant time.
 306        *  (It is only swapping a pointer, an integer, and an instance of the @c
 307        *  Compare type (which itself is often stateless and empty), so it should
 308        *  be quite fast.)
 309        *  Note that the global std::swap() function is specialized such that
 310        *  std::swap(s1,s2) will feed to this function.
 311        */
 312       void
 313 #ifdef __GXX_EXPERIMENTAL_CXX0X__
 314       swap(multiset&& __x)
 315 #else
 316       swap(multiset& __x)
 317 #endif
 318       { _M_t.swap(__x._M_t); }
 319
 320       // insert/erase
 321       /**
 322        *  @brief Inserts an element into the %multiset.
 323        *  @param  x  Element to be inserted.
 324        *  @return An iterator that points to the inserted element.
 325        *
 326        *  This function inserts an element into the %multiset.  Contrary
 327        *  to a std::set the %multiset does not rely on unique keys and thus
 328        *  multiple copies of the same element can be inserted.
 329        *
 330        *  Insertion requires logarithmic time.
 331        */
 332       iterator
 333       insert(const value_type& __x)
 334       { return _M_t._M_insert_equal(__x); }
 335
 336       /**
 337        *  @brief Inserts an element into the %multiset.
 338        *  @param  position  An iterator that serves as a hint as to where the
 339        *                    element should be inserted.
 340        *  @param  x  Element to be inserted.
 341        *  @return An iterator that points to the inserted element.
 342        *
 343        *  This function inserts an element into the %multiset.  Contrary
 344        *  to a std::set the %multiset does not rely on unique keys and thus
 345        *  multiple copies of the same element can be inserted.
 346        *
 347        *  Note that the first parameter is only a hint and can potentially
 348        *  improve the performance of the insertion process.  A bad hint would
 349        *  cause no gains in efficiency.
 350        *
 351        *  See http://gcc.gnu.org/onlinedocs/libstdc++/23_containers/howto.html#4
 352        *  for more on "hinting".
 353        *
 354        *  Insertion requires logarithmic time (if the hint is not taken).
 355        */
 356       iterator
 357       insert(iterator __position, const value_type& __x)
 358       { return _M_t._M_insert_equal_(__position, __x); }
 359
 360       /**
 361        *  @brief A template function that attemps to insert a range of elements.
 362        *  @param  first  Iterator pointing to the start of the range to be
 363        *                 inserted.
 364        *  @param  last  Iterator pointing to the end of the range.
 365        *
 366        *  Complexity similar to that of the range constructor.
 367        */
 368       template<typename _InputIterator>
 369         void
 370         insert(_InputIterator __first, _InputIterator __last)
 371         { _M_t._M_insert_equal(__first, __last); }
 372
 373       /**
 374        *  @brief Erases an element from a %multiset.
 375        *  @param  position  An iterator pointing to the element to be erased.
 376        *
 377        *  This function erases an element, pointed to by the given iterator,
 378        *  from a %multiset.  Note that this function only erases the element,
 379        *  and that if the element is itself a pointer, the pointed-to memory is
 380        *  not touched in any way.  Managing the pointer is the user's
 381        *  responsibilty.
 382        */
 383       void
 384       erase(iterator __position)
 385       { _M_t.erase(__position); }
 386
 387       /**
 388        *  @brief Erases elements according to the provided key.
 389        *  @param  x  Key of element to be erased.
 390        *  @return  The number of elements erased.
 391        *
 392        *  This function erases all elements located by the given key from a
 393        *  %multiset.
 394        *  Note that this function only erases the element, and that if
 395        *  the element is itself a pointer, the pointed-to memory is not touched
 396        *  in any way.  Managing the pointer is the user's responsibilty.
 397        */
 398       size_type
 399       erase(const key_type& __x)
 400       { return _M_t.erase(__x); }
 401
 402       /**
 403        *  @brief Erases a [first,last) range of elements from a %multiset.
 404        *  @param  first  Iterator pointing to the start of the range to be
 405        *                 erased.
 406        *  @param  last  Iterator pointing to the end of the range to be erased.
 407        *
 408        *  This function erases a sequence of elements from a %multiset.
 409        *  Note that this function only erases the elements, and that if
 410        *  the elements themselves are pointers, the pointed-to memory is not
 411        *  touched in any way.  Managing the pointer is the user's responsibilty.
 412        */
 413       void
 414       erase(iterator __first, iterator __last)
 415       { _M_t.erase(__first, __last); }
 416
 417       /**
 418        *  Erases all elements in a %multiset.  Note that this function only
 419        *  erases the elements, and that if the elements themselves are pointers,
 420        *  the pointed-to memory is not touched in any way.  Managing the pointer
 421        *  is the user's responsibilty.
 422        */
 423       void
 424       clear()
 425       { _M_t.clear(); }
 426
 427       // multiset operations:
 428
 429       /**
 430        *  @brief Finds the number of elements with given key.
 431        *  @param  x  Key of elements to be located.
 432        *  @return Number of elements with specified key.
 433        */
 434       size_type
 435       count(const key_type& __x) const
 436       { return _M_t.count(__x); }
 437
 438       // _GLIBCXX_RESOLVE_LIB_DEFECTS
 439       // 214.  set::find() missing const overload
 440       //@{
 441       /**
 442        *  @brief Tries to locate an element in a %set.
 443        *  @param  x  Element to be located.
 444        *  @return  Iterator pointing to sought-after element, or end() if not
 445        *           found.
 446        *
 447        *  This function takes a key and tries to locate the element with which
 448        *  the key matches.  If successful the function returns an iterator
 449        *  pointing to the sought after element.  If unsuccessful it returns the
 450        *  past-the-end ( @c end() ) iterator.
 451        */
 452       iterator
 453       find(const key_type& __x)
 454       { return _M_t.find(__x); }
 455
 456       const_iterator
 457       find(const key_type& __x) const
 458       { return _M_t.find(__x); }
 459       //@}
 460
 461       //@{
 462       /**
 463        *  @brief Finds the beginning of a subsequence matching given key.
 464        *  @param  x  Key to be located.
 465        *  @return  Iterator pointing to first element equal to or greater
 466        *           than key, or end().
 467        *
 468        *  This function returns the first element of a subsequence of elements
 469        *  that matches the given key.  If unsuccessful it returns an iterator
 470        *  pointing to the first element that has a greater value than given key
 471        *  or end() if no such element exists.
 472        */
 473       iterator
 474       lower_bound(const key_type& __x)
 475       { return _M_t.lower_bound(__x); }
 476
 477       const_iterator
 478       lower_bound(const key_type& __x) const
 479       { return _M_t.lower_bound(__x); }
 480       //@}
 481
 482       //@{
 483       /**
 484        *  @brief Finds the end of a subsequence matching given key.
 485        *  @param  x  Key to be located.
 486        *  @return Iterator pointing to the first element
 487        *          greater than key, or end().
 488        */
 489       iterator
 490       upper_bound(const key_type& __x)
 491       { return _M_t.upper_bound(__x); }
 492
 493       const_iterator
 494       upper_bound(const key_type& __x) const
 495       { return _M_t.upper_bound(__x); }
 496       //@}
 497
 498       //@{
 499       /**
 500        *  @brief Finds a subsequence matching given key.
 501        *  @param  x  Key to be located.
 502        *  @return  Pair of iterators that possibly points to the subsequence
 503        *           matching given key.
 504        *
 505        *  This function is equivalent to
 506        *  @code
 507        *    std::make_pair(c.lower_bound(val),
 508        *                   c.upper_bound(val))
 509        *  @endcode
 510        *  (but is faster than making the calls separately).
 511        *
 512        *  This function probably only makes sense for multisets.
 513        */
 514       std::pair<iterator, iterator>
 515       equal_range(const key_type& __x)
 516       { return _M_t.equal_range(__x); }
 517
 518       std::pair<const_iterator, const_iterator>
 519       equal_range(const key_type& __x) const
 520       { return _M_t.equal_range(__x); }
 521
 522       template<typename _K1, typename _C1, typename _A1>
 523         friend bool
 524         operator==(const multiset<_K1, _C1, _A1>&,
 525                    const multiset<_K1, _C1, _A1>&);
 526
 527       template<typename _K1, typename _C1, typename _A1>
 528         friend bool
 529         operator< (const multiset<_K1, _C1, _A1>&,
 530                    const multiset<_K1, _C1, _A1>&);
 531     };
 532
 533   /**
 534    *  @brief  Multiset equality comparison.
 535    *  @param  x  A %multiset.
 536    *  @param  y  A %multiset of the same type as @a x.
 537    *  @return  True iff the size and elements of the multisets are equal.
 538    *
 539    *  This is an equivalence relation.  It is linear in the size of the
 540    *  multisets.
 541    *  Multisets are considered equivalent if their sizes are equal, and if
 542    *  corresponding elements compare equal.
 543   */
 544   template<typename _Key, typename _Compare, typename _Alloc>
 545     inline bool
 546     operator==(const multiset<_Key, _Compare, _Alloc>& __x,
 547                const multiset<_Key, _Compare, _Alloc>& __y)
 548     { return __x._M_t == __y._M_t; }
 549
 550   /**
 551    *  @brief  Multiset ordering relation.
 552    *  @param  x  A %multiset.
 553    *  @param  y  A %multiset of the same type as @a x.
 554    *  @return  True iff @a x is lexicographically less than @a y.
 555    *
 556    *  This is a total ordering relation.  It is linear in the size of the
 557    *  maps.  The elements must be comparable with @c <.
 558    *
 559    *  See std::lexicographical_compare() for how the determination is made.
 560   */
 561   template<typename _Key, typename _Compare, typename _Alloc>
 562     inline bool
 563     operator<(const multiset<_Key, _Compare, _Alloc>& __x,
 564               const multiset<_Key, _Compare, _Alloc>& __y)
 565     { return __x._M_t < __y._M_t; }
 566
 567   ///  Returns !(x == y).
 568   template<typename _Key, typename _Compare, typename _Alloc>
 569     inline bool
 570     operator!=(const multiset<_Key, _Compare, _Alloc>& __x,
 571                const multiset<_Key, _Compare, _Alloc>& __y)
 572     { return !(__x == __y); }
 573
 574   ///  Returns y < x.
 575   template<typename _Key, typename _Compare, typename _Alloc>
 576     inline bool
 577     operator>(const multiset<_Key,_Compare,_Alloc>& __x,
 578               const multiset<_Key,_Compare,_Alloc>& __y)
 579     { return __y < __x; }
 580
 581   ///  Returns !(y < x)
 582   template<typename _Key, typename _Compare, typename _Alloc>
 583     inline bool
 584     operator<=(const multiset<_Key, _Compare, _Alloc>& __x,
 585                const multiset<_Key, _Compare, _Alloc>& __y)
 586     { return !(__y < __x); }
 587
 588   ///  Returns !(x < y)
 589   template<typename _Key, typename _Compare, typename _Alloc>
 590     inline bool
 591     operator>=(const multiset<_Key, _Compare, _Alloc>& __x,
 592                const multiset<_Key, _Compare, _Alloc>& __y)
 593     { return !(__x < __y); }
 594
 595   /// See std::multiset::swap().
 596   template<typename _Key, typename _Compare, typename _Alloc>
 597     inline void
 598     swap(multiset<_Key, _Compare, _Alloc>& __x,
 599          multiset<_Key, _Compare, _Alloc>& __y)
 600     { __x.swap(__y); }
 601
 602 #ifdef __GXX_EXPERIMENTAL_CXX0X__
 603   template<typename _Key, typename _Compare, typename _Alloc>
 604     inline void
 605     swap(multiset<_Key, _Compare, _Alloc>&& __x,
 606          multiset<_Key, _Compare, _Alloc>& __y)
 607     { __x.swap(__y); }
 608
 609   template<typename _Key, typename _Compare, typename _Alloc>
 610     inline void
 611     swap(multiset<_Key, _Compare, _Alloc>& __x,
 612          multiset<_Key, _Compare, _Alloc>&& __y)
 613     { __x.swap(__y); }
 614 #endif
 615
 616 _GLIBCXX_END_NESTED_NAMESPACE
 617
 618 #endif /* _STL_MULTISET_H */