1 // Multiset implementation -*- C++ -*- 2 3 // Copyright (C) 2001-2017 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 * 27 * Copyright (c) 1994 28 * Hewlett-Packard Company 29 * 30 * Permission to use, copy, modify, distribute and sell this software 31 * and its documentation for any purpose is hereby granted without fee, 32 * provided that the above copyright notice appear in all copies and 33 * that both that copyright notice and this permission notice appear 34 * in supporting documentation. Hewlett-Packard Company makes no 35 * representations about the suitability of this software for any 36 * purpose. It is provided "as is" without express or implied warranty. 37 * 38 * 39 * Copyright (c) 1996 40 * Silicon Graphics Computer Systems, Inc. 41 * 42 * Permission to use, copy, modify, distribute and sell this software 43 * and its documentation for any purpose is hereby granted without fee, 44 * provided that the above copyright notice appear in all copies and 45 * that both that copyright notice and this permission notice appear 46 * in supporting documentation. Silicon Graphics makes no 47 * representations about the suitability of this software for any 48 * purpose. It is provided "as is" without express or implied warranty. 49 */ 50 51 /** @file bits/stl_multiset.h 52 * This is an internal header file, included by other library headers. 53 * Do not attempt to use it directly. @headername{set} 54 */ 55 56 #ifndef _STL_MULTISET_H 57 #define _STL_MULTISET_H 1 58 59 #include <bits/concept_check.h> 60 #if __cplusplus >= 201103L 61 #include <initializer_list> 62 #endif 63 64 namespace std _GLIBCXX_VISIBILITY(default) 65 { 66 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER 67 68 template<typename _Key, typename _Compare, typename _Alloc> 69 class set; 70 71 /** 72 * @brief A standard container made up of elements, which can be retrieved 73 * in logarithmic time. 74 * 75 * @ingroup associative_containers 76 * 77 * 78 * @tparam _Key Type of key objects. 79 * @tparam _Compare Comparison function object type, defaults to less<_Key>. 80 * @tparam _Alloc Allocator type, defaults to allocator<_Key>. 81 * 82 * Meets the requirements of a <a href="tables.html#65">container</a>, a 83 * <a href="tables.html#66">reversible container</a>, and an 84 * <a href="tables.html#69">associative container</a> (using equivalent 85 * keys). For a @c multiset<Key> the key_type and value_type are Key. 86 * 87 * Multisets support bidirectional iterators. 88 * 89 * The private tree data is declared exactly the same way for set and 90 * multiset; the distinction is made entirely in how the tree functions are 91 * called (*_unique versus *_equal, same as the standard). 92 */ 93 template <typename _Key, typename _Compare = std::less<_Key>, 94 typename _Alloc = std::allocator<_Key> > 95 class multiset 96 { 97 #ifdef _GLIBCXX_CONCEPT_CHECKS 98 // concept requirements 99 typedef typename _Alloc::value_type _Alloc_value_type; 100 # if __cplusplus < 201103L 101 __glibcxx_class_requires(_Key, _SGIAssignableConcept) 102 # endif 103 __glibcxx_class_requires4(_Compare, bool, _Key, _Key, 104 _BinaryFunctionConcept) 105 __glibcxx_class_requires2(_Key, _Alloc_value_type, _SameTypeConcept) 106 #endif 107 108 public: 109 // typedefs: 110 typedef _Key key_type; 111 typedef _Key value_type; 112 typedef _Compare key_compare; 113 typedef _Compare value_compare; 114 typedef _Alloc allocator_type; 115 116 private: 117 /// This turns a red-black tree into a [multi]set. 118 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template 119 rebind<_Key>::other _Key_alloc_type; 120 121 typedef _Rb_tree<key_type, value_type, _Identity<value_type>, 122 key_compare, _Key_alloc_type> _Rep_type; 123 /// The actual tree structure. 124 _Rep_type _M_t; 125 126 typedef __gnu_cxx::__alloc_traits<_Key_alloc_type> _Alloc_traits; 127 128 public: 129 typedef typename _Alloc_traits::pointer pointer; 130 typedef typename _Alloc_traits::const_pointer const_pointer; 131 typedef typename _Alloc_traits::reference reference; 132 typedef typename _Alloc_traits::const_reference const_reference; 133 // _GLIBCXX_RESOLVE_LIB_DEFECTS 134 // DR 103. set::iterator is required to be modifiable, 135 // but this allows modification of keys. 136 typedef typename _Rep_type::const_iterator iterator; 137 typedef typename _Rep_type::const_iterator const_iterator; 138 typedef typename _Rep_type::const_reverse_iterator reverse_iterator; 139 typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator; 140 typedef typename _Rep_type::size_type size_type; 141 typedef typename _Rep_type::difference_type difference_type; 142 143 #if __cplusplus > 201402L 144 using node_type = typename _Rep_type::node_type; 145 #endif 146 147 // allocation/deallocation 148 /** 149 * @brief Default constructor creates no elements. 150 */ 151 #if __cplusplus < 201103L 152 multiset() : _M_t() { } 153 #else 154 multiset() = default; 155 #endif 156 157 /** 158 * @brief Creates a %multiset with no elements. 159 * @param __comp Comparator to use. 160 * @param __a An allocator object. 161 */ 162 explicit 163 multiset(const _Compare& __comp, 164 const allocator_type& __a = allocator_type()) 165 : _M_t(__comp, _Key_alloc_type(__a)) { } 166 167 /** 168 * @brief Builds a %multiset from a range. 169 * @param __first An input iterator. 170 * @param __last An input iterator. 171 * 172 * Create a %multiset consisting of copies of the elements from 173 * [first,last). This is linear in N if the range is already sorted, 174 * and NlogN otherwise (where N is distance(__first,__last)). 175 */ 176 template<typename _InputIterator> 177 multiset(_InputIterator __first, _InputIterator __last) 178 : _M_t() 179 { _M_t._M_insert_equal(__first, __last); } 180 181 /** 182 * @brief Builds a %multiset from a range. 183 * @param __first An input iterator. 184 * @param __last An input iterator. 185 * @param __comp A comparison functor. 186 * @param __a An allocator object. 187 * 188 * Create a %multiset consisting of copies of the elements from 189 * [__first,__last). This is linear in N if the range is already sorted, 190 * and NlogN otherwise (where N is distance(__first,__last)). 191 */ 192 template<typename _InputIterator> 193 multiset(_InputIterator __first, _InputIterator __last, 194 const _Compare& __comp, 195 const allocator_type& __a = allocator_type()) 196 : _M_t(__comp, _Key_alloc_type(__a)) 197 { _M_t._M_insert_equal(__first, __last); } 198 199 /** 200 * @brief %Multiset copy constructor. 201 * 202 * Whether the allocator is copied depends on the allocator traits. 203 */ 204 #if __cplusplus < 201103L 205 multiset(const multiset& __x) 206 : _M_t(__x._M_t) { } 207 #else 208 multiset(const multiset&) = default; 209 210 /** 211 * @brief %Multiset move constructor. 212 * 213 * The newly-created %multiset contains the exact contents of the 214 * moved instance. The moved instance is a valid, but unspecified 215 * %multiset. 216 */ 217 multiset(multiset&&) = default; 218 219 /** 220 * @brief Builds a %multiset from an initializer_list. 221 * @param __l An initializer_list. 222 * @param __comp A comparison functor. 223 * @param __a An allocator object. 224 * 225 * Create a %multiset consisting of copies of the elements from 226 * the list. This is linear in N if the list is already sorted, 227 * and NlogN otherwise (where N is @a __l.size()). 228 */ 229 multiset(initializer_list<value_type> __l, 230 const _Compare& __comp = _Compare(), 231 const allocator_type& __a = allocator_type()) 232 : _M_t(__comp, _Key_alloc_type(__a)) 233 { _M_t._M_insert_equal(__l.begin(), __l.end()); } 234 235 /// Allocator-extended default constructor. 236 explicit 237 multiset(const allocator_type& __a) 238 : _M_t(_Compare(), _Key_alloc_type(__a)) { } 239 240 /// Allocator-extended copy constructor. 241 multiset(const multiset& __m, const allocator_type& __a) 242 : _M_t(__m._M_t, _Key_alloc_type(__a)) { } 243 244 /// Allocator-extended move constructor. 245 multiset(multiset&& __m, const allocator_type& __a) 246 noexcept(is_nothrow_copy_constructible<_Compare>::value 247 && _Alloc_traits::_S_always_equal()) 248 : _M_t(std::move(__m._M_t), _Key_alloc_type(__a)) { } 249 250 /// Allocator-extended initialier-list constructor. 251 multiset(initializer_list<value_type> __l, const allocator_type& __a) 252 : _M_t(_Compare(), _Key_alloc_type(__a)) 253 { _M_t._M_insert_equal(__l.begin(), __l.end()); } 254 255 /// Allocator-extended range constructor. 256 template<typename _InputIterator> 257 multiset(_InputIterator __first, _InputIterator __last, 258 const allocator_type& __a) 259 : _M_t(_Compare(), _Key_alloc_type(__a)) 260 { _M_t._M_insert_equal(__first, __last); } 261 262 /** 263 * The dtor only erases the elements, and note that if the elements 264 * themselves are pointers, the pointed-to memory is not touched in any 265 * way. Managing the pointer is the user's responsibility. 266 */ 267 ~multiset() = default; 268 #endif 269 270 /** 271 * @brief %Multiset assignment operator. 272 * 273 * Whether the allocator is copied depends on the allocator traits. 274 */ 275 #if __cplusplus < 201103L 276 multiset& 277 operator=(const multiset& __x) 278 { 279 _M_t = __x._M_t; 280 return *this; 281 } 282 #else 283 multiset& 284 operator=(const multiset&) = default; 285 286 /// Move assignment operator. 287 multiset& 288 operator=(multiset&&) = default; 289 290 /** 291 * @brief %Multiset list assignment operator. 292 * @param __l An initializer_list. 293 * 294 * This function fills a %multiset with copies of the elements in the 295 * initializer list @a __l. 296 * 297 * Note that the assignment completely changes the %multiset and 298 * that the resulting %multiset's size is the same as the number 299 * of elements assigned. 300 */ 301 multiset& 302 operator=(initializer_list<value_type> __l) 303 { 304 _M_t._M_assign_equal(__l.begin(), __l.end()); 305 return *this; 306 } 307 #endif 308 309 // accessors: 310 311 /// Returns the comparison object. 312 key_compare 313 key_comp() const 314 { return _M_t.key_comp(); } 315 /// Returns the comparison object. 316 value_compare 317 value_comp() const 318 { return _M_t.key_comp(); } 319 /// Returns the memory allocation object. 320 allocator_type 321 get_allocator() const _GLIBCXX_NOEXCEPT 322 { return allocator_type(_M_t.get_allocator()); } 323 324 /** 325 * Returns a read-only (constant) iterator that points to the first 326 * element in the %multiset. Iteration is done in ascending order 327 * according to the keys. 328 */ 329 iterator 330 begin() const _GLIBCXX_NOEXCEPT 331 { return _M_t.begin(); } 332 333 /** 334 * Returns a read-only (constant) iterator that points one past the last 335 * element in the %multiset. Iteration is done in ascending order 336 * according to the keys. 337 */ 338 iterator 339 end() const _GLIBCXX_NOEXCEPT 340 { return _M_t.end(); } 341 342 /** 343 * Returns a read-only (constant) reverse iterator that points to the 344 * last element in the %multiset. Iteration is done in descending order 345 * according to the keys. 346 */ 347 reverse_iterator 348 rbegin() const _GLIBCXX_NOEXCEPT 349 { return _M_t.rbegin(); } 350 351 /** 352 * Returns a read-only (constant) reverse iterator that points to the 353 * last element in the %multiset. Iteration is done in descending order 354 * according to the keys. 355 */ 356 reverse_iterator 357 rend() const _GLIBCXX_NOEXCEPT 358 { return _M_t.rend(); } 359 360 #if __cplusplus >= 201103L 361 /** 362 * Returns a read-only (constant) iterator that points to the first 363 * element in the %multiset. Iteration is done in ascending order 364 * according to the keys. 365 */ 366 iterator 367 cbegin() const noexcept 368 { return _M_t.begin(); } 369 370 /** 371 * Returns a read-only (constant) iterator that points one past the last 372 * element in the %multiset. Iteration is done in ascending order 373 * according to the keys. 374 */ 375 iterator 376 cend() const noexcept 377 { return _M_t.end(); } 378 379 /** 380 * Returns a read-only (constant) reverse iterator that points to the 381 * last element in the %multiset. Iteration is done in descending order 382 * according to the keys. 383 */ 384 reverse_iterator 385 crbegin() const noexcept 386 { return _M_t.rbegin(); } 387 388 /** 389 * Returns a read-only (constant) reverse iterator that points to the 390 * last element in the %multiset. Iteration is done in descending order 391 * according to the keys. 392 */ 393 reverse_iterator 394 crend() const noexcept 395 { return _M_t.rend(); } 396 #endif 397 398 /// Returns true if the %set is empty. 399 bool 400 empty() const _GLIBCXX_NOEXCEPT 401 { return _M_t.empty(); } 402 403 /// Returns the size of the %set. 404 size_type 405 size() const _GLIBCXX_NOEXCEPT 406 { return _M_t.size(); } 407 408 /// Returns the maximum size of the %set. 409 size_type 410 max_size() const _GLIBCXX_NOEXCEPT 411 { return _M_t.max_size(); } 412 413 /** 414 * @brief Swaps data with another %multiset. 415 * @param __x A %multiset of the same element and allocator types. 416 * 417 * This exchanges the elements between two multisets in constant time. 418 * (It is only swapping a pointer, an integer, and an instance of the @c 419 * Compare type (which itself is often stateless and empty), so it should 420 * be quite fast.) 421 * Note that the global std::swap() function is specialized such that 422 * std::swap(s1,s2) will feed to this function. 423 * 424 * Whether the allocators are swapped depends on the allocator traits. 425 */ 426 void 427 swap(multiset& __x) 428 _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value) 429 { _M_t.swap(__x._M_t); } 430 431 // insert/erase 432 #if __cplusplus >= 201103L 433 /** 434 * @brief Builds and inserts an element into the %multiset. 435 * @param __args Arguments used to generate the element instance to be 436 * inserted. 437 * @return An iterator that points to the inserted element. 438 * 439 * This function inserts an element into the %multiset. Contrary 440 * to a std::set the %multiset does not rely on unique keys and thus 441 * multiple copies of the same element can be inserted. 442 * 443 * Insertion requires logarithmic time. 444 */ 445 template<typename... _Args> 446 iterator 447 emplace(_Args&&... __args) 448 { return _M_t._M_emplace_equal(std::forward<_Args>(__args)...); } 449 450 /** 451 * @brief Builds and inserts an element into the %multiset. 452 * @param __pos An iterator that serves as a hint as to where the 453 * element should be inserted. 454 * @param __args Arguments used to generate the element instance to be 455 * inserted. 456 * @return An iterator that points to the inserted element. 457 * 458 * This function inserts an element into the %multiset. Contrary 459 * to a std::set the %multiset does not rely on unique keys and thus 460 * multiple copies of the same element can be inserted. 461 * 462 * Note that the first parameter is only a hint and can potentially 463 * improve the performance of the insertion process. A bad hint would 464 * cause no gains in efficiency. 465 * 466 * See https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints 467 * for more on @a hinting. 468 * 469 * Insertion requires logarithmic time (if the hint is not taken). 470 */ 471 template<typename... _Args> 472 iterator 473 emplace_hint(const_iterator __pos, _Args&&... __args) 474 { 475 return _M_t._M_emplace_hint_equal(__pos, 476 std::forward<_Args>(__args)...); 477 } 478 #endif 479 480 /** 481 * @brief Inserts an element into the %multiset. 482 * @param __x Element to be inserted. 483 * @return An iterator that points to the inserted element. 484 * 485 * This function inserts an element into the %multiset. Contrary 486 * to a std::set the %multiset does not rely on unique keys and thus 487 * multiple copies of the same element can be inserted. 488 * 489 * Insertion requires logarithmic time. 490 */ 491 iterator 492 insert(const value_type& __x) 493 { return _M_t._M_insert_equal(__x); } 494 495 #if __cplusplus >= 201103L 496 iterator 497 insert(value_type&& __x) 498 { return _M_t._M_insert_equal(std::move(__x)); } 499 #endif 500 501 /** 502 * @brief Inserts an element into the %multiset. 503 * @param __position An iterator that serves as a hint as to where the 504 * element should be inserted. 505 * @param __x Element to be inserted. 506 * @return An iterator that points to the inserted element. 507 * 508 * This function inserts an element into the %multiset. Contrary 509 * to a std::set the %multiset does not rely on unique keys and thus 510 * multiple copies of the same element can be inserted. 511 * 512 * Note that the first parameter is only a hint and can potentially 513 * improve the performance of the insertion process. A bad hint would 514 * cause no gains in efficiency. 515 * 516 * See https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints 517 * for more on @a hinting. 518 * 519 * Insertion requires logarithmic time (if the hint is not taken). 520 */ 521 iterator 522 insert(const_iterator __position, const value_type& __x) 523 { return _M_t._M_insert_equal_(__position, __x); } 524 525 #if __cplusplus >= 201103L 526 iterator 527 insert(const_iterator __position, value_type&& __x) 528 { return _M_t._M_insert_equal_(__position, std::move(__x)); } 529 #endif 530 531 /** 532 * @brief A template function that tries to insert a range of elements. 533 * @param __first Iterator pointing to the start of the range to be 534 * inserted. 535 * @param __last Iterator pointing to the end of the range. 536 * 537 * Complexity similar to that of the range constructor. 538 */ 539 template<typename _InputIterator> 540 void 541 insert(_InputIterator __first, _InputIterator __last) 542 { _M_t._M_insert_equal(__first, __last); } 543 544 #if __cplusplus >= 201103L 545 /** 546 * @brief Attempts to insert a list of elements into the %multiset. 547 * @param __l A std::initializer_list<value_type> of elements 548 * to be inserted. 549 * 550 * Complexity similar to that of the range constructor. 551 */ 552 void 553 insert(initializer_list<value_type> __l) 554 { this->insert(__l.begin(), __l.end()); } 555 #endif 556 557 #if __cplusplus > 201402L 558 /// Extract a node. 559 node_type 560 extract(const_iterator __pos) 561 { 562 __glibcxx_assert(__pos != end()); 563 return _M_t.extract(__pos); 564 } 565 566 /// Extract a node. 567 node_type 568 extract(const key_type& __x) 569 { return _M_t.extract(__x); } 570 571 /// Re-insert an extracted node. 572 iterator 573 insert(node_type&& __nh) 574 { return _M_t._M_reinsert_node_equal(std::move(__nh)); } 575 576 /// Re-insert an extracted node. 577 iterator 578 insert(const_iterator __hint, node_type&& __nh) 579 { return _M_t._M_reinsert_node_hint_equal(__hint, std::move(__nh)); } 580 581 template<typename, typename> 582 friend class _Rb_tree_merge_helper; 583 584 template<typename _Compare1> 585 void 586 merge(multiset<_Key, _Compare1, _Alloc>& __source) 587 { 588 using _Merge_helper = _Rb_tree_merge_helper<multiset, _Compare1>; 589 _M_t._M_merge_equal(_Merge_helper::_S_get_tree(__source)); 590 } 591 592 template<typename _Compare1> 593 void 594 merge(multiset<_Key, _Compare1, _Alloc>&& __source) 595 { merge(__source); } 596 597 template<typename _Compare1> 598 void 599 merge(set<_Key, _Compare1, _Alloc>& __source) 600 { 601 using _Merge_helper = _Rb_tree_merge_helper<multiset, _Compare1>; 602 _M_t._M_merge_equal(_Merge_helper::_S_get_tree(__source)); 603 } 604 605 template<typename _Compare1> 606 void 607 merge(set<_Key, _Compare1, _Alloc>&& __source) 608 { merge(__source); } 609 #endif // C++17 610 611 #if __cplusplus >= 201103L 612 // _GLIBCXX_RESOLVE_LIB_DEFECTS 613 // DR 130. Associative erase should return an iterator. 614 /** 615 * @brief Erases an element from a %multiset. 616 * @param __position An iterator pointing to the element to be erased. 617 * @return An iterator pointing to the element immediately following 618 * @a position prior to the element being erased. If no such 619 * element exists, end() is returned. 620 * 621 * This function erases an element, pointed to by the given iterator, 622 * from a %multiset. Note that this function only erases the element, 623 * and that if the element is itself a pointer, the pointed-to memory is 624 * not touched in any way. Managing the pointer is the user's 625 * responsibility. 626 */ 627 _GLIBCXX_ABI_TAG_CXX11 628 iterator 629 erase(const_iterator __position) 630 { return _M_t.erase(__position); } 631 #else 632 /** 633 * @brief Erases an element from a %multiset. 634 * @param __position An iterator pointing to the element to be erased. 635 * 636 * This function erases an element, pointed to by the given iterator, 637 * from a %multiset. Note that this function only erases the element, 638 * and that if the element is itself a pointer, the pointed-to memory is 639 * not touched in any way. Managing the pointer is the user's 640 * responsibility. 641 */ 642 void 643 erase(iterator __position) 644 { _M_t.erase(__position); } 645 #endif 646 647 /** 648 * @brief Erases elements according to the provided key. 649 * @param __x Key of element to be erased. 650 * @return The number of elements erased. 651 * 652 * This function erases all elements located by the given key from a 653 * %multiset. 654 * Note that this function only erases the element, and that if 655 * the element is itself a pointer, the pointed-to memory is not touched 656 * in any way. Managing the pointer is the user's responsibility. 657 */ 658 size_type 659 erase(const key_type& __x) 660 { return _M_t.erase(__x); } 661 662 #if __cplusplus >= 201103L 663 // _GLIBCXX_RESOLVE_LIB_DEFECTS 664 // DR 130. Associative erase should return an iterator. 665 /** 666 * @brief Erases a [first,last) range of elements from a %multiset. 667 * @param __first Iterator pointing to the start of the range to be 668 * erased. 669 * @param __last Iterator pointing to the end of the range to 670 * be erased. 671 * @return The iterator @a last. 672 * 673 * This function erases a sequence of elements from a %multiset. 674 * Note that this function only erases the elements, and that if 675 * the elements themselves are pointers, the pointed-to memory is not 676 * touched in any way. Managing the pointer is the user's 677 * responsibility. 678 */ 679 _GLIBCXX_ABI_TAG_CXX11 680 iterator 681 erase(const_iterator __first, const_iterator __last) 682 { return _M_t.erase(__first, __last); } 683 #else 684 /** 685 * @brief Erases a [first,last) range of elements from a %multiset. 686 * @param first Iterator pointing to the start of the range to be 687 * erased. 688 * @param last Iterator pointing to the end of the range to be erased. 689 * 690 * This function erases a sequence of elements from a %multiset. 691 * Note that this function only erases the elements, and that if 692 * the elements themselves are pointers, the pointed-to memory is not 693 * touched in any way. Managing the pointer is the user's 694 * responsibility. 695 */ 696 void 697 erase(iterator __first, iterator __last) 698 { _M_t.erase(__first, __last); } 699 #endif 700 701 /** 702 * Erases all elements in a %multiset. Note that this function only 703 * erases the elements, and that if the elements themselves are pointers, 704 * the pointed-to memory is not touched in any way. Managing the pointer 705 * is the user's responsibility. 706 */ 707 void 708 clear() _GLIBCXX_NOEXCEPT 709 { _M_t.clear(); } 710 711 // multiset operations: 712 713 //@{ 714 /** 715 * @brief Finds the number of elements with given key. 716 * @param __x Key of elements to be located. 717 * @return Number of elements with specified key. 718 */ 719 size_type 720 count(const key_type& __x) const 721 { return _M_t.count(__x); } 722 723 #if __cplusplus > 201103L 724 template<typename _Kt> 725 auto 726 count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x)) 727 { return _M_t._M_count_tr(__x); } 728 #endif 729 //@} 730 731 // _GLIBCXX_RESOLVE_LIB_DEFECTS 732 // 214. set::find() missing const overload 733 //@{ 734 /** 735 * @brief Tries to locate an element in a %set. 736 * @param __x Element to be located. 737 * @return Iterator pointing to sought-after element, or end() if not 738 * found. 739 * 740 * This function takes a key and tries to locate the element with which 741 * the key matches. If successful the function returns an iterator 742 * pointing to the sought after element. If unsuccessful it returns the 743 * past-the-end ( @c end() ) iterator. 744 */ 745 iterator 746 find(const key_type& __x) 747 { return _M_t.find(__x); } 748 749 const_iterator 750 find(const key_type& __x) const 751 { return _M_t.find(__x); } 752 753 #if __cplusplus > 201103L 754 template<typename _Kt> 755 auto 756 find(const _Kt& __x) 757 -> decltype(iterator{_M_t._M_find_tr(__x)}) 758 { return iterator{_M_t._M_find_tr(__x)}; } 759 760 template<typename _Kt> 761 auto 762 find(const _Kt& __x) const 763 -> decltype(const_iterator{_M_t._M_find_tr(__x)}) 764 { return const_iterator{_M_t._M_find_tr(__x)}; } 765 #endif 766 //@} 767 768 //@{ 769 /** 770 * @brief Finds the beginning of a subsequence matching given key. 771 * @param __x Key to be located. 772 * @return Iterator pointing to first element equal to or greater 773 * than key, or end(). 774 * 775 * This function returns the first element of a subsequence of elements 776 * that matches the given key. If unsuccessful it returns an iterator 777 * pointing to the first element that has a greater value than given key 778 * or end() if no such element exists. 779 */ 780 iterator 781 lower_bound(const key_type& __x) 782 { return _M_t.lower_bound(__x); } 783 784 const_iterator 785 lower_bound(const key_type& __x) const 786 { return _M_t.lower_bound(__x); } 787 788 #if __cplusplus > 201103L 789 template<typename _Kt> 790 auto 791 lower_bound(const _Kt& __x) 792 -> decltype(iterator(_M_t._M_lower_bound_tr(__x))) 793 { return iterator(_M_t._M_lower_bound_tr(__x)); } 794 795 template<typename _Kt> 796 auto 797 lower_bound(const _Kt& __x) const 798 -> decltype(iterator(_M_t._M_lower_bound_tr(__x))) 799 { return iterator(_M_t._M_lower_bound_tr(__x)); } 800 #endif 801 //@} 802 803 //@{ 804 /** 805 * @brief Finds the end of a subsequence matching given key. 806 * @param __x Key to be located. 807 * @return Iterator pointing to the first element 808 * greater than key, or end(). 809 */ 810 iterator 811 upper_bound(const key_type& __x) 812 { return _M_t.upper_bound(__x); } 813 814 const_iterator 815 upper_bound(const key_type& __x) const 816 { return _M_t.upper_bound(__x); } 817 818 #if __cplusplus > 201103L 819 template<typename _Kt> 820 auto 821 upper_bound(const _Kt& __x) 822 -> decltype(iterator(_M_t._M_upper_bound_tr(__x))) 823 { return iterator(_M_t._M_upper_bound_tr(__x)); } 824 825 template<typename _Kt> 826 auto 827 upper_bound(const _Kt& __x) const 828 -> decltype(iterator(_M_t._M_upper_bound_tr(__x))) 829 { return iterator(_M_t._M_upper_bound_tr(__x)); } 830 #endif 831 //@} 832 833 //@{ 834 /** 835 * @brief Finds a subsequence matching given key. 836 * @param __x Key to be located. 837 * @return Pair of iterators that possibly points to the subsequence 838 * matching given key. 839 * 840 * This function is equivalent to 841 * @code 842 * std::make_pair(c.lower_bound(val), 843 * c.upper_bound(val)) 844 * @endcode 845 * (but is faster than making the calls separately). 846 * 847 * This function probably only makes sense for multisets. 848 */ 849 std::pair<iterator, iterator> 850 equal_range(const key_type& __x) 851 { return _M_t.equal_range(__x); } 852 853 std::pair<const_iterator, const_iterator> 854 equal_range(const key_type& __x) const 855 { return _M_t.equal_range(__x); } 856 857 #if __cplusplus > 201103L 858 template<typename _Kt> 859 auto 860 equal_range(const _Kt& __x) 861 -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x))) 862 { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); } 863 864 template<typename _Kt> 865 auto 866 equal_range(const _Kt& __x) const 867 -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x))) 868 { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); } 869 #endif 870 //@} 871 872 template<typename _K1, typename _C1, typename _A1> 873 friend bool 874 operator==(const multiset<_K1, _C1, _A1>&, 875 const multiset<_K1, _C1, _A1>&); 876 877 template<typename _K1, typename _C1, typename _A1> 878 friend bool 879 operator< (const multiset<_K1, _C1, _A1>&, 880 const multiset<_K1, _C1, _A1>&); 881 }; 882 883 /** 884 * @brief Multiset equality comparison. 885 * @param __x A %multiset. 886 * @param __y A %multiset of the same type as @a __x. 887 * @return True iff the size and elements of the multisets are equal. 888 * 889 * This is an equivalence relation. It is linear in the size of the 890 * multisets. 891 * Multisets are considered equivalent if their sizes are equal, and if 892 * corresponding elements compare equal. 893 */ 894 template<typename _Key, typename _Compare, typename _Alloc> 895 inline bool 896 operator==(const multiset<_Key, _Compare, _Alloc>& __x, 897 const multiset<_Key, _Compare, _Alloc>& __y) 898 { return __x._M_t == __y._M_t; } 899 900 /** 901 * @brief Multiset ordering relation. 902 * @param __x A %multiset. 903 * @param __y A %multiset of the same type as @a __x. 904 * @return True iff @a __x is lexicographically less than @a __y. 905 * 906 * This is a total ordering relation. It is linear in the size of the 907 * sets. The elements must be comparable with @c <. 908 * 909 * See std::lexicographical_compare() for how the determination is made. 910 */ 911 template<typename _Key, typename _Compare, typename _Alloc> 912 inline bool 913 operator<(const multiset<_Key, _Compare, _Alloc>& __x, 914 const multiset<_Key, _Compare, _Alloc>& __y) 915 { return __x._M_t < __y._M_t; } 916 917 /// Returns !(x == y). 918 template<typename _Key, typename _Compare, typename _Alloc> 919 inline bool 920 operator!=(const multiset<_Key, _Compare, _Alloc>& __x, 921 const multiset<_Key, _Compare, _Alloc>& __y) 922 { return !(__x == __y); } 923 924 /// Returns y < x. 925 template<typename _Key, typename _Compare, typename _Alloc> 926 inline bool 927 operator>(const multiset<_Key,_Compare,_Alloc>& __x, 928 const multiset<_Key,_Compare,_Alloc>& __y) 929 { return __y < __x; } 930 931 /// Returns !(y < x) 932 template<typename _Key, typename _Compare, typename _Alloc> 933 inline bool 934 operator<=(const multiset<_Key, _Compare, _Alloc>& __x, 935 const multiset<_Key, _Compare, _Alloc>& __y) 936 { return !(__y < __x); } 937 938 /// Returns !(x < y) 939 template<typename _Key, typename _Compare, typename _Alloc> 940 inline bool 941 operator>=(const multiset<_Key, _Compare, _Alloc>& __x, 942 const multiset<_Key, _Compare, _Alloc>& __y) 943 { return !(__x < __y); } 944 945 /// See std::multiset::swap(). 946 template<typename _Key, typename _Compare, typename _Alloc> 947 inline void 948 swap(multiset<_Key, _Compare, _Alloc>& __x, 949 multiset<_Key, _Compare, _Alloc>& __y) 950 _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y))) 951 { __x.swap(__y); } 952 953 _GLIBCXX_END_NAMESPACE_CONTAINER 954 955 #if __cplusplus > 201402L 956 _GLIBCXX_BEGIN_NAMESPACE_VERSION 957 // Allow std::multiset access to internals of compatible sets. 958 template<typename _Val, typename _Cmp1, typename _Alloc, typename _Cmp2> 959 struct 960 _Rb_tree_merge_helper<_GLIBCXX_STD_C::multiset<_Val, _Cmp1, _Alloc>, 961 _Cmp2> 962 { 963 private: 964 friend class _GLIBCXX_STD_C::multiset<_Val, _Cmp1, _Alloc>; 965 966 static auto& 967 _S_get_tree(_GLIBCXX_STD_C::set<_Val, _Cmp2, _Alloc>& __set) 968 { return __set._M_t; } 969 970 static auto& 971 _S_get_tree(_GLIBCXX_STD_C::multiset<_Val, _Cmp2, _Alloc>& __set) 972 { return __set._M_t; } 973 }; 974 _GLIBCXX_END_NAMESPACE_VERSION 975 #endif // C++17 976 977 } // namespace std 978 979 #endif /* _STL_MULTISET_H */ 980