1// Multiset implementation -*- C++ -*- 2 3// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 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 3, 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// Under Section 7 of GPL version 3, you are granted additional 18// permissions described in the GCC Runtime Library Exception, version 19// 3.1, as published by the Free Software Foundation. 20 21// You should have received a copy of the GNU General Public License and 22// a copy of the GCC Runtime Library Exception along with this program; 23// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24// <http://www.gnu.org/licenses/>. 25 26/* 27 * 28 * Copyright (c) 1994 29 * Hewlett-Packard Company 30 * 31 * Permission to use, copy, modify, distribute and sell this software 32 * and its documentation for any purpose is hereby granted without fee, 33 * provided that the above copyright notice appear in all copies and 34 * that both that copyright notice and this permission notice appear 35 * in supporting documentation. Hewlett-Packard Company makes no 36 * representations about the suitability of this software for any 37 * purpose. It is provided "as is" without express or implied warranty. 38 * 39 * 40 * Copyright (c) 1996 41 * Silicon Graphics Computer Systems, Inc. 42 * 43 * Permission to use, copy, modify, distribute and sell this software 44 * and its documentation for any purpose is hereby granted without fee, 45 * provided that the above copyright notice appear in all copies and 46 * that both that copyright notice and this permission notice appear 47 * in supporting documentation. Silicon Graphics makes no 48 * representations about the suitability of this software for any 49 * purpose. It is provided "as is" without express or implied warranty. 50 */ 51 52/** @file stl_multiset.h 53 * This is an internal header file, included by other library headers. 54 * You should not attempt to use it directly. 55 */ 56 57#ifndef _STL_MULTISET_H 58#define _STL_MULTISET_H 1 59 60#include <bits/concept_check.h> 61#include <initializer_list> 62 63_GLIBCXX_BEGIN_NESTED_NAMESPACE(std, _GLIBCXX_STD_D) 64 65 /** 66 * @brief A standard container made up of elements, which can be retrieved 67 * in logarithmic time. 68 * 69 * @ingroup associative_containers 70 * 71 * Meets the requirements of a <a href="tables.html#65">container</a>, a 72 * <a href="tables.html#66">reversible container</a>, and an 73 * <a href="tables.html#69">associative container</a> (using equivalent 74 * keys). For a @c multiset<Key> the key_type and value_type are Key. 75 * 76 * Multisets support bidirectional iterators. 77 * 78 * The private tree data is declared exactly the same way for set and 79 * multiset; the distinction is made entirely in how the tree functions are 80 * called (*_unique versus *_equal, same as the standard). 81 */ 82 template <typename _Key, typename _Compare = std::less<_Key>, 83 typename _Alloc = std::allocator<_Key> > 84 class multiset 85 { 86 // concept requirements 87 typedef typename _Alloc::value_type _Alloc_value_type; 88 __glibcxx_class_requires(_Key, _SGIAssignableConcept) 89 __glibcxx_class_requires4(_Compare, bool, _Key, _Key, 90 _BinaryFunctionConcept) 91 __glibcxx_class_requires2(_Key, _Alloc_value_type, _SameTypeConcept) 92 93 public: 94 // typedefs: 95 typedef _Key key_type; 96 typedef _Key value_type; 97 typedef _Compare key_compare; 98 typedef _Compare value_compare; 99 typedef _Alloc allocator_type; 100 101 private: 102 /// This turns a red-black tree into a [multi]set. 103 typedef typename _Alloc::template rebind<_Key>::other _Key_alloc_type; 104 105 typedef _Rb_tree<key_type, value_type, _Identity<value_type>, 106 key_compare, _Key_alloc_type> _Rep_type; 107 /// The actual tree structure. 108 _Rep_type _M_t; 109 110 public: 111 typedef typename _Key_alloc_type::pointer pointer; 112 typedef typename _Key_alloc_type::const_pointer const_pointer; 113 typedef typename _Key_alloc_type::reference reference; 114 typedef typename _Key_alloc_type::const_reference const_reference; 115 // _GLIBCXX_RESOLVE_LIB_DEFECTS 116 // DR 103. set::iterator is required to be modifiable, 117 // but this allows modification of keys. 118 typedef typename _Rep_type::const_iterator iterator; 119 typedef typename _Rep_type::const_iterator const_iterator; 120 typedef typename _Rep_type::const_reverse_iterator reverse_iterator; 121 typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator; 122 typedef typename _Rep_type::size_type size_type; 123 typedef typename _Rep_type::difference_type difference_type; 124 125 // allocation/deallocation 126 /** 127 * @brief Default constructor creates no elements. 128 */ 129 multiset() 130 : _M_t() { } 131 132 /** 133 * @brief Creates a %multiset with no elements. 134 * @param comp Comparator to use. 135 * @param a An allocator object. 136 */ 137 explicit 138 multiset(const _Compare& __comp, 139 const allocator_type& __a = allocator_type()) 140 : _M_t(__comp, __a) { } 141 142 /** 143 * @brief Builds a %multiset from a range. 144 * @param first An input iterator. 145 * @param last An input iterator. 146 * 147 * Create a %multiset consisting of copies of the elements from 148 * [first,last). This is linear in N if the range is already sorted, 149 * and NlogN otherwise (where N is distance(first,last)). 150 */ 151 template<typename _InputIterator> 152 multiset(_InputIterator __first, _InputIterator __last) 153 : _M_t() 154 { _M_t._M_insert_equal(__first, __last); } 155 156 /** 157 * @brief Builds a %multiset from a range. 158 * @param first An input iterator. 159 * @param last An input iterator. 160 * @param comp A comparison functor. 161 * @param a An allocator object. 162 * 163 * Create a %multiset consisting of copies of the elements from 164 * [first,last). This is linear in N if the range is already sorted, 165 * and NlogN otherwise (where N is distance(first,last)). 166 */ 167 template<typename _InputIterator> 168 multiset(_InputIterator __first, _InputIterator __last, 169 const _Compare& __comp, 170 const allocator_type& __a = allocator_type()) 171 : _M_t(__comp, __a) 172 { _M_t._M_insert_equal(__first, __last); } 173 174 /** 175 * @brief %Multiset copy constructor. 176 * @param x A %multiset of identical element and allocator types. 177 * 178 * The newly-created %multiset uses a copy of the allocation object used 179 * by @a x. 180 */ 181 multiset(const multiset& __x) 182 : _M_t(__x._M_t) { } 183 184#ifdef __GXX_EXPERIMENTAL_CXX0X__ 185 /** 186 * @brief %Multiset move constructor. 187 * @param x A %multiset of identical element and allocator types. 188 * 189 * The newly-created %multiset contains the exact contents of @a x. 190 * The contents of @a x are a valid, but unspecified %multiset. 191 */ 192 multiset(multiset&& __x) 193 : _M_t(std::forward<_Rep_type>(__x._M_t)) { } 194 195 /** 196 * @brief Builds a %multiset from an initializer_list. 197 * @param l An initializer_list. 198 * @param comp A comparison functor. 199 * @param a An allocator object. 200 * 201 * Create a %multiset consisting of copies of the elements from 202 * the list. This is linear in N if the list is already sorted, 203 * and NlogN otherwise (where N is @a l.size()). 204 */ 205 multiset(initializer_list<value_type> __l, 206 const _Compare& __comp = _Compare(), 207 const allocator_type& __a = allocator_type()) 208 : _M_t(__comp, __a) 209 { _M_t._M_insert_equal(__l.begin(), __l.end()); } 210#endif 211 212 /** 213 * @brief %Multiset assignment operator. 214 * @param x A %multiset of identical element and allocator types. 215 * 216 * All the elements of @a x are copied, but unlike the copy constructor, 217 * the allocator object is not copied. 218 */ 219 multiset& 220 operator=(const multiset& __x) 221 { 222 _M_t = __x._M_t; 223 return *this; 224 } 225 226#ifdef __GXX_EXPERIMENTAL_CXX0X__ 227 /** 228 * @brief %Multiset move assignment operator. 229 * @param x A %multiset of identical element and allocator types. 230 * 231 * The contents of @a x are moved into this %multiset (without copying). 232 * @a x is a valid, but unspecified %multiset. 233 */ 234 multiset& 235 operator=(multiset&& __x) 236 { 237 // NB: DR 1204. 238 // NB: DR 675. 239 this->clear(); 240 this->swap(__x); 241 return *this; 242 } 243 244 /** 245 * @brief %Multiset list assignment operator. 246 * @param l An initializer_list. 247 * 248 * This function fills a %multiset with copies of the elements in the 249 * initializer list @a l. 250 * 251 * Note that the assignment completely changes the %multiset and 252 * that the resulting %multiset's size is the same as the number 253 * of elements assigned. Old data may be lost. 254 */ 255 multiset& 256 operator=(initializer_list<value_type> __l) 257 { 258 this->clear(); 259 this->insert(__l.begin(), __l.end()); 260 return *this; 261 } 262#endif 263 264 // accessors: 265 266 /// Returns the comparison object. 267 key_compare 268 key_comp() const 269 { return _M_t.key_comp(); } 270 /// Returns the comparison object. 271 value_compare 272 value_comp() const 273 { return _M_t.key_comp(); } 274 /// Returns the memory allocation object. 275 allocator_type 276 get_allocator() const 277 { return _M_t.get_allocator(); } 278 279 /** 280 * Returns a read-only (constant) iterator that points to the first 281 * element in the %multiset. Iteration is done in ascending order 282 * according to the keys. 283 */ 284 iterator 285 begin() const 286 { return _M_t.begin(); } 287 288 /** 289 * Returns a read-only (constant) iterator that points one past the last 290 * element in the %multiset. Iteration is done in ascending order 291 * according to the keys. 292 */ 293 iterator 294 end() const 295 { return _M_t.end(); } 296 297 /** 298 * Returns a read-only (constant) reverse iterator that points to the 299 * last element in the %multiset. Iteration is done in descending order 300 * according to the keys. 301 */ 302 reverse_iterator 303 rbegin() const 304 { return _M_t.rbegin(); } 305 306 /** 307 * Returns a read-only (constant) reverse iterator that points to the 308 * last element in the %multiset. Iteration is done in descending order 309 * according to the keys. 310 */ 311 reverse_iterator 312 rend() const 313 { return _M_t.rend(); } 314 315#ifdef __GXX_EXPERIMENTAL_CXX0X__ 316 /** 317 * Returns a read-only (constant) iterator that points to the first 318 * element in the %multiset. Iteration is done in ascending order 319 * according to the keys. 320 */ 321 iterator 322 cbegin() const 323 { return _M_t.begin(); } 324 325 /** 326 * Returns a read-only (constant) iterator that points one past the last 327 * element in the %multiset. Iteration is done in ascending order 328 * according to the keys. 329 */ 330 iterator 331 cend() const 332 { return _M_t.end(); } 333 334 /** 335 * Returns a read-only (constant) reverse iterator that points to the 336 * last element in the %multiset. Iteration is done in descending order 337 * according to the keys. 338 */ 339 reverse_iterator 340 crbegin() const 341 { return _M_t.rbegin(); } 342 343 /** 344 * Returns a read-only (constant) reverse iterator that points to the 345 * last element in the %multiset. Iteration is done in descending order 346 * according to the keys. 347 */ 348 reverse_iterator 349 crend() const 350 { return _M_t.rend(); } 351#endif 352 353 /// Returns true if the %set is empty. 354 bool 355 empty() const 356 { return _M_t.empty(); } 357 358 /// Returns the size of the %set. 359 size_type 360 size() const 361 { return _M_t.size(); } 362 363 /// Returns the maximum size of the %set. 364 size_type 365 max_size() const 366 { return _M_t.max_size(); } 367 368 /** 369 * @brief Swaps data with another %multiset. 370 * @param x A %multiset of the same element and allocator types. 371 * 372 * This exchanges the elements between two multisets in constant time. 373 * (It is only swapping a pointer, an integer, and an instance of the @c 374 * Compare type (which itself is often stateless and empty), so it should 375 * be quite fast.) 376 * Note that the global std::swap() function is specialized such that 377 * std::swap(s1,s2) will feed to this function. 378 */ 379 void 380 swap(multiset& __x) 381 { _M_t.swap(__x._M_t); } 382 383 // insert/erase 384 /** 385 * @brief Inserts an element into the %multiset. 386 * @param x Element to be inserted. 387 * @return An iterator that points to the inserted element. 388 * 389 * This function inserts an element into the %multiset. Contrary 390 * to a std::set the %multiset does not rely on unique keys and thus 391 * multiple copies of the same element can be inserted. 392 * 393 * Insertion requires logarithmic time. 394 */ 395 iterator 396 insert(const value_type& __x) 397 { return _M_t._M_insert_equal(__x); } 398 399 /** 400 * @brief Inserts an element into the %multiset. 401 * @param position An iterator that serves as a hint as to where the 402 * element should be inserted. 403 * @param x Element to be inserted. 404 * @return An iterator that points to the inserted element. 405 * 406 * This function inserts an element into the %multiset. Contrary 407 * to a std::set the %multiset does not rely on unique keys and thus 408 * multiple copies of the same element can be inserted. 409 * 410 * Note that the first parameter is only a hint and can potentially 411 * improve the performance of the insertion process. A bad hint would 412 * cause no gains in efficiency. 413 * 414 * See http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html 415 * for more on @a hinting. 416 * 417 * Insertion requires logarithmic time (if the hint is not taken). 418 */ 419 iterator 420 insert(iterator __position, const value_type& __x) 421 { return _M_t._M_insert_equal_(__position, __x); } 422 423 /** 424 * @brief A template function that tries to insert a range of elements. 425 * @param first Iterator pointing to the start of the range to be 426 * inserted. 427 * @param last Iterator pointing to the end of the range. 428 * 429 * Complexity similar to that of the range constructor. 430 */ 431 template<typename _InputIterator> 432 void 433 insert(_InputIterator __first, _InputIterator __last) 434 { _M_t._M_insert_equal(__first, __last); } 435 436#ifdef __GXX_EXPERIMENTAL_CXX0X__ 437 /** 438 * @brief Attempts to insert a list of elements into the %multiset. 439 * @param list A std::initializer_list<value_type> of elements 440 * to be inserted. 441 * 442 * Complexity similar to that of the range constructor. 443 */ 444 void 445 insert(initializer_list<value_type> __l) 446 { this->insert(__l.begin(), __l.end()); } 447#endif 448 449#ifdef __GXX_EXPERIMENTAL_CXX0X__ 450 // _GLIBCXX_RESOLVE_LIB_DEFECTS 451 // DR 130. Associative erase should return an iterator. 452 /** 453 * @brief Erases an element from a %multiset. 454 * @param position An iterator pointing to the element to be erased. 455 * @return An iterator pointing to the element immediately following 456 * @a position prior to the element being erased. If no such 457 * element exists, end() is returned. 458 * 459 * This function erases an element, pointed to by the given iterator, 460 * from a %multiset. Note that this function only erases the element, 461 * and that if the element is itself a pointer, the pointed-to memory is 462 * not touched in any way. Managing the pointer is the user's 463 * responsibility. 464 */ 465 iterator 466 erase(iterator __position) 467 { return _M_t.erase(__position); } 468#else 469 /** 470 * @brief Erases an element from a %multiset. 471 * @param position An iterator pointing to the element to be erased. 472 * 473 * This function erases an element, pointed to by the given iterator, 474 * from a %multiset. Note that this function only erases the element, 475 * and that if the element is itself a pointer, the pointed-to memory is 476 * not touched in any way. Managing the pointer is the user's 477 * responsibility. 478 */ 479 void 480 erase(iterator __position) 481 { _M_t.erase(__position); } 482#endif 483 484 /** 485 * @brief Erases elements according to the provided key. 486 * @param x Key of element to be erased. 487 * @return The number of elements erased. 488 * 489 * This function erases all elements located by the given key from a 490 * %multiset. 491 * Note that this function only erases the element, and that if 492 * the element is itself a pointer, the pointed-to memory is not touched 493 * in any way. Managing the pointer is the user's responsibility. 494 */ 495 size_type 496 erase(const key_type& __x) 497 { return _M_t.erase(__x); } 498 499#ifdef __GXX_EXPERIMENTAL_CXX0X__ 500 // _GLIBCXX_RESOLVE_LIB_DEFECTS 501 // DR 130. Associative erase should return an iterator. 502 /** 503 * @brief Erases a [first,last) range of elements from a %multiset. 504 * @param first Iterator pointing to the start of the range to be 505 * erased. 506 * @param last Iterator pointing to the end of the range to be erased. 507 * @return The iterator @a last. 508 * 509 * This function erases a sequence of elements from a %multiset. 510 * Note that this function only erases the elements, and that if 511 * the elements themselves are pointers, the pointed-to memory is not 512 * touched in any way. Managing the pointer is the user's responsibility. 513 */ 514 iterator 515 erase(iterator __first, iterator __last) 516 { return _M_t.erase(__first, __last); } 517#else 518 /** 519 * @brief Erases a [first,last) range of elements from a %multiset. 520 * @param first Iterator pointing to the start of the range to be 521 * erased. 522 * @param last Iterator pointing to the end of the range to be erased. 523 * 524 * This function erases a sequence of elements from a %multiset. 525 * Note that this function only erases the elements, and that if 526 * the elements themselves are pointers, the pointed-to memory is not 527 * touched in any way. Managing the pointer is the user's responsibility. 528 */ 529 void 530 erase(iterator __first, iterator __last) 531 { _M_t.erase(__first, __last); } 532#endif 533 534 /** 535 * Erases all elements in a %multiset. Note that this function only 536 * erases the elements, and that if the elements themselves are pointers, 537 * the pointed-to memory is not touched in any way. Managing the pointer 538 * is the user's responsibility. 539 */ 540 void 541 clear() 542 { _M_t.clear(); } 543 544 // multiset operations: 545 546 /** 547 * @brief Finds the number of elements with given key. 548 * @param x Key of elements to be located. 549 * @return Number of elements with specified key. 550 */ 551 size_type 552 count(const key_type& __x) const 553 { return _M_t.count(__x); } 554 555 // _GLIBCXX_RESOLVE_LIB_DEFECTS 556 // 214. set::find() missing const overload 557 //@{ 558 /** 559 * @brief Tries to locate an element in a %set. 560 * @param x Element to be located. 561 * @return Iterator pointing to sought-after element, or end() if not 562 * found. 563 * 564 * This function takes a key and tries to locate the element with which 565 * the key matches. If successful the function returns an iterator 566 * pointing to the sought after element. If unsuccessful it returns the 567 * past-the-end ( @c end() ) iterator. 568 */ 569 iterator 570 find(const key_type& __x) 571 { return _M_t.find(__x); } 572 573 const_iterator 574 find(const key_type& __x) const 575 { return _M_t.find(__x); } 576 //@} 577 578 //@{ 579 /** 580 * @brief Finds the beginning of a subsequence matching given key. 581 * @param x Key to be located. 582 * @return Iterator pointing to first element equal to or greater 583 * than key, or end(). 584 * 585 * This function returns the first element of a subsequence of elements 586 * that matches the given key. If unsuccessful it returns an iterator 587 * pointing to the first element that has a greater value than given key 588 * or end() if no such element exists. 589 */ 590 iterator 591 lower_bound(const key_type& __x) 592 { return _M_t.lower_bound(__x); } 593 594 const_iterator 595 lower_bound(const key_type& __x) const 596 { return _M_t.lower_bound(__x); } 597 //@} 598 599 //@{ 600 /** 601 * @brief Finds the end of a subsequence matching given key. 602 * @param x Key to be located. 603 * @return Iterator pointing to the first element 604 * greater than key, or end(). 605 */ 606 iterator 607 upper_bound(const key_type& __x) 608 { return _M_t.upper_bound(__x); } 609 610 const_iterator 611 upper_bound(const key_type& __x) const 612 { return _M_t.upper_bound(__x); } 613 //@} 614 615 //@{ 616 /** 617 * @brief Finds a subsequence matching given key. 618 * @param x Key to be located. 619 * @return Pair of iterators that possibly points to the subsequence 620 * matching given key. 621 * 622 * This function is equivalent to 623 * @code 624 * std::make_pair(c.lower_bound(val), 625 * c.upper_bound(val)) 626 * @endcode 627 * (but is faster than making the calls separately). 628 * 629 * This function probably only makes sense for multisets. 630 */ 631 std::pair<iterator, iterator> 632 equal_range(const key_type& __x) 633 { return _M_t.equal_range(__x); } 634 635 std::pair<const_iterator, const_iterator> 636 equal_range(const key_type& __x) const 637 { return _M_t.equal_range(__x); } 638 639 template<typename _K1, typename _C1, typename _A1> 640 friend bool 641 operator==(const multiset<_K1, _C1, _A1>&, 642 const multiset<_K1, _C1, _A1>&); 643 644 template<typename _K1, typename _C1, typename _A1> 645 friend bool 646 operator< (const multiset<_K1, _C1, _A1>&, 647 const multiset<_K1, _C1, _A1>&); 648 }; 649 650 /** 651 * @brief Multiset equality comparison. 652 * @param x A %multiset. 653 * @param y A %multiset of the same type as @a x. 654 * @return True iff the size and elements of the multisets are equal. 655 * 656 * This is an equivalence relation. It is linear in the size of the 657 * multisets. 658 * Multisets are considered equivalent if their sizes are equal, and if 659 * corresponding elements compare equal. 660 */ 661 template<typename _Key, typename _Compare, typename _Alloc> 662 inline bool 663 operator==(const multiset<_Key, _Compare, _Alloc>& __x, 664 const multiset<_Key, _Compare, _Alloc>& __y) 665 { return __x._M_t == __y._M_t; } 666 667 /** 668 * @brief Multiset ordering relation. 669 * @param x A %multiset. 670 * @param y A %multiset of the same type as @a x. 671 * @return True iff @a x is lexicographically less than @a y. 672 * 673 * This is a total ordering relation. It is linear in the size of the 674 * maps. The elements must be comparable with @c <. 675 * 676 * See std::lexicographical_compare() for how the determination is made. 677 */ 678 template<typename _Key, typename _Compare, typename _Alloc> 679 inline bool 680 operator<(const multiset<_Key, _Compare, _Alloc>& __x, 681 const multiset<_Key, _Compare, _Alloc>& __y) 682 { return __x._M_t < __y._M_t; } 683 684 /// Returns !(x == y). 685 template<typename _Key, typename _Compare, typename _Alloc> 686 inline bool 687 operator!=(const multiset<_Key, _Compare, _Alloc>& __x, 688 const multiset<_Key, _Compare, _Alloc>& __y) 689 { return !(__x == __y); } 690 691 /// Returns y < x. 692 template<typename _Key, typename _Compare, typename _Alloc> 693 inline bool 694 operator>(const multiset<_Key,_Compare,_Alloc>& __x, 695 const multiset<_Key,_Compare,_Alloc>& __y) 696 { return __y < __x; } 697 698 /// Returns !(y < x) 699 template<typename _Key, typename _Compare, typename _Alloc> 700 inline bool 701 operator<=(const multiset<_Key, _Compare, _Alloc>& __x, 702 const multiset<_Key, _Compare, _Alloc>& __y) 703 { return !(__y < __x); } 704 705 /// Returns !(x < y) 706 template<typename _Key, typename _Compare, typename _Alloc> 707 inline bool 708 operator>=(const multiset<_Key, _Compare, _Alloc>& __x, 709 const multiset<_Key, _Compare, _Alloc>& __y) 710 { return !(__x < __y); } 711 712 /// See std::multiset::swap(). 713 template<typename _Key, typename _Compare, typename _Alloc> 714 inline void 715 swap(multiset<_Key, _Compare, _Alloc>& __x, 716 multiset<_Key, _Compare, _Alloc>& __y) 717 { __x.swap(__y); } 718 719_GLIBCXX_END_NESTED_NAMESPACE 720 721#endif /* _STL_MULTISET_H */ 722