1// Multimap implementation -*- C++ -*- 2 3// Copyright (C) 2001-2014 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) 1996,1997 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_multimap.h 52 * This is an internal header file, included by other library headers. 53 * Do not attempt to use it directly. @headername{map} 54 */ 55 56#ifndef _STL_MULTIMAP_H 57#define _STL_MULTIMAP_H 1 58 59#include <bits/concept_check.h> 60#if __cplusplus >= 201103L 61#include <initializer_list> 62#endif 63 64namespace std _GLIBCXX_VISIBILITY(default) 65{ 66_GLIBCXX_BEGIN_NAMESPACE_CONTAINER 67 68 /** 69 * @brief A standard container made up of (key,value) pairs, which can be 70 * retrieved based on a key, in logarithmic time. 71 * 72 * @ingroup associative_containers 73 * 74 * @tparam _Key Type of key objects. 75 * @tparam _Tp Type of mapped objects. 76 * @tparam _Compare Comparison function object type, defaults to less<_Key>. 77 * @tparam _Alloc Allocator type, defaults to 78 * allocator<pair<const _Key, _Tp>. 79 * 80 * Meets the requirements of a <a href="tables.html#65">container</a>, a 81 * <a href="tables.html#66">reversible container</a>, and an 82 * <a href="tables.html#69">associative container</a> (using equivalent 83 * keys). For a @c multimap<Key,T> the key_type is Key, the mapped_type 84 * is T, and the value_type is std::pair<const Key,T>. 85 * 86 * Multimaps support bidirectional iterators. 87 * 88 * The private tree data is declared exactly the same way for map and 89 * multimap; the distinction is made entirely in how the tree functions are 90 * called (*_unique versus *_equal, same as the standard). 91 */ 92 template <typename _Key, typename _Tp, 93 typename _Compare = std::less<_Key>, 94 typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > > 95 class multimap 96 { 97 public: 98 typedef _Key key_type; 99 typedef _Tp mapped_type; 100 typedef std::pair<const _Key, _Tp> value_type; 101 typedef _Compare key_compare; 102 typedef _Alloc allocator_type; 103 104 private: 105 // concept requirements 106 typedef typename _Alloc::value_type _Alloc_value_type; 107 __glibcxx_class_requires(_Tp, _SGIAssignableConcept) 108 __glibcxx_class_requires4(_Compare, bool, _Key, _Key, 109 _BinaryFunctionConcept) 110 __glibcxx_class_requires2(value_type, _Alloc_value_type, _SameTypeConcept) 111 112 public: 113 class value_compare 114 : public std::binary_function<value_type, value_type, bool> 115 { 116 friend class multimap<_Key, _Tp, _Compare, _Alloc>; 117 protected: 118 _Compare comp; 119 120 value_compare(_Compare __c) 121 : comp(__c) { } 122 123 public: 124 bool operator()(const value_type& __x, const value_type& __y) const 125 { return comp(__x.first, __y.first); } 126 }; 127 128 private: 129 /// This turns a red-black tree into a [multi]map. 130 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template 131 rebind<value_type>::other _Pair_alloc_type; 132 133 typedef _Rb_tree<key_type, value_type, _Select1st<value_type>, 134 key_compare, _Pair_alloc_type> _Rep_type; 135 /// The actual tree structure. 136 _Rep_type _M_t; 137 138 typedef __gnu_cxx::__alloc_traits<_Pair_alloc_type> _Alloc_traits; 139 140 public: 141 // many of these are specified differently in ISO, but the following are 142 // "functionally equivalent" 143 typedef typename _Alloc_traits::pointer pointer; 144 typedef typename _Alloc_traits::const_pointer const_pointer; 145 typedef typename _Alloc_traits::reference reference; 146 typedef typename _Alloc_traits::const_reference const_reference; 147 typedef typename _Rep_type::iterator iterator; 148 typedef typename _Rep_type::const_iterator const_iterator; 149 typedef typename _Rep_type::size_type size_type; 150 typedef typename _Rep_type::difference_type difference_type; 151 typedef typename _Rep_type::reverse_iterator reverse_iterator; 152 typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator; 153 154 // [23.3.2] construct/copy/destroy 155 // (get_allocator() is also listed in this section) 156 157 /** 158 * @brief Default constructor creates no elements. 159 */ 160 multimap() 161 : _M_t() { } 162 163 /** 164 * @brief Creates a %multimap with no elements. 165 * @param __comp A comparison object. 166 * @param __a An allocator object. 167 */ 168 explicit 169 multimap(const _Compare& __comp, 170 const allocator_type& __a = allocator_type()) 171 : _M_t(__comp, _Pair_alloc_type(__a)) { } 172 173 /** 174 * @brief %Multimap copy constructor. 175 * @param __x A %multimap of identical element and allocator types. 176 * 177 * The newly-created %multimap uses a copy of the allocation object 178 * used by @a __x. 179 */ 180 multimap(const multimap& __x) 181 : _M_t(__x._M_t) { } 182 183#if __cplusplus >= 201103L 184 /** 185 * @brief %Multimap move constructor. 186 * @param __x A %multimap of identical element and allocator types. 187 * 188 * The newly-created %multimap contains the exact contents of @a __x. 189 * The contents of @a __x are a valid, but unspecified %multimap. 190 */ 191 multimap(multimap&& __x) 192 noexcept(is_nothrow_copy_constructible<_Compare>::value) 193 : _M_t(std::move(__x._M_t)) { } 194 195 /** 196 * @brief Builds a %multimap 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 %multimap consisting of copies of the elements from 202 * the initializer_list. This is linear in N if the list is already 203 * sorted, and NlogN otherwise (where N is @a __l.size()). 204 */ 205 multimap(initializer_list<value_type> __l, 206 const _Compare& __comp = _Compare(), 207 const allocator_type& __a = allocator_type()) 208 : _M_t(__comp, _Pair_alloc_type(__a)) 209 { _M_t._M_insert_equal(__l.begin(), __l.end()); } 210 211 /// Allocator-extended default constructor. 212 explicit 213 multimap(const allocator_type& __a) 214 : _M_t(_Compare(), _Pair_alloc_type(__a)) { } 215 216 /// Allocator-extended copy constructor. 217 multimap(const multimap& __m, const allocator_type& __a) 218 : _M_t(__m._M_t, _Pair_alloc_type(__a)) { } 219 220 /// Allocator-extended move constructor. 221 multimap(multimap&& __m, const allocator_type& __a) 222 noexcept(is_nothrow_copy_constructible<_Compare>::value 223 && _Alloc_traits::_S_always_equal()) 224 : _M_t(std::move(__m._M_t), _Pair_alloc_type(__a)) { } 225 226 /// Allocator-extended initialier-list constructor. 227 multimap(initializer_list<value_type> __l, const allocator_type& __a) 228 : _M_t(_Compare(), _Pair_alloc_type(__a)) 229 { _M_t._M_insert_equal(__l.begin(), __l.end()); } 230 231 /// Allocator-extended range constructor. 232 template<typename _InputIterator> 233 multimap(_InputIterator __first, _InputIterator __last, 234 const allocator_type& __a) 235 : _M_t(_Compare(), _Pair_alloc_type(__a)) 236 { _M_t._M_insert_equal(__first, __last); } 237#endif 238 239 /** 240 * @brief Builds a %multimap from a range. 241 * @param __first An input iterator. 242 * @param __last An input iterator. 243 * 244 * Create a %multimap consisting of copies of the elements from 245 * [__first,__last). This is linear in N if the range is already sorted, 246 * and NlogN otherwise (where N is distance(__first,__last)). 247 */ 248 template<typename _InputIterator> 249 multimap(_InputIterator __first, _InputIterator __last) 250 : _M_t() 251 { _M_t._M_insert_equal(__first, __last); } 252 253 /** 254 * @brief Builds a %multimap from a range. 255 * @param __first An input iterator. 256 * @param __last An input iterator. 257 * @param __comp A comparison functor. 258 * @param __a An allocator object. 259 * 260 * Create a %multimap consisting of copies of the elements from 261 * [__first,__last). This is linear in N if the range is already sorted, 262 * and NlogN otherwise (where N is distance(__first,__last)). 263 */ 264 template<typename _InputIterator> 265 multimap(_InputIterator __first, _InputIterator __last, 266 const _Compare& __comp, 267 const allocator_type& __a = allocator_type()) 268 : _M_t(__comp, _Pair_alloc_type(__a)) 269 { _M_t._M_insert_equal(__first, __last); } 270 271 // FIXME There is no dtor declared, but we should have something generated 272 // by Doxygen. I don't know what tags to add to this paragraph to make 273 // that happen: 274 /** 275 * The dtor only erases the elements, and note that if the elements 276 * themselves are pointers, the pointed-to memory is not touched in any 277 * way. Managing the pointer is the user's responsibility. 278 */ 279 280 /** 281 * @brief %Multimap assignment operator. 282 * @param __x A %multimap of identical element and allocator types. 283 * 284 * All the elements of @a __x are copied, but unlike the copy 285 * constructor, the allocator object is not copied. 286 */ 287 multimap& 288 operator=(const multimap& __x) 289 { 290 _M_t = __x._M_t; 291 return *this; 292 } 293 294#if __cplusplus >= 201103L 295 /** 296 * @brief %Multimap move assignment operator. 297 * @param __x A %multimap of identical element and allocator types. 298 * 299 * The contents of @a __x are moved into this multimap (without copying 300 * if the allocators compare equal or get moved on assignment). 301 * Afterwards @a __x is in a valid, but unspecified state. 302 */ 303 multimap& 304 operator=(multimap&& __x) noexcept(_Alloc_traits::_S_nothrow_move()) 305 { 306 if (!_M_t._M_move_assign(__x._M_t)) 307 { 308 // The rvalue's allocator cannot be moved and is not equal, 309 // so we need to individually move each element. 310 clear(); 311 insert(std::__make_move_if_noexcept_iterator(__x.begin()), 312 std::__make_move_if_noexcept_iterator(__x.end())); 313 __x.clear(); 314 } 315 return *this; 316 } 317 318 /** 319 * @brief %Multimap list assignment operator. 320 * @param __l An initializer_list. 321 * 322 * This function fills a %multimap with copies of the elements 323 * in the initializer list @a __l. 324 * 325 * Note that the assignment completely changes the %multimap and 326 * that the resulting %multimap's size is the same as the number 327 * of elements assigned. Old data may be lost. 328 */ 329 multimap& 330 operator=(initializer_list<value_type> __l) 331 { 332 this->clear(); 333 this->insert(__l.begin(), __l.end()); 334 return *this; 335 } 336#endif 337 338 /// Get a copy of the memory allocation object. 339 allocator_type 340 get_allocator() const _GLIBCXX_NOEXCEPT 341 { return allocator_type(_M_t.get_allocator()); } 342 343 // iterators 344 /** 345 * Returns a read/write iterator that points to the first pair in the 346 * %multimap. Iteration is done in ascending order according to the 347 * keys. 348 */ 349 iterator 350 begin() _GLIBCXX_NOEXCEPT 351 { return _M_t.begin(); } 352 353 /** 354 * Returns a read-only (constant) iterator that points to the first pair 355 * in the %multimap. Iteration is done in ascending order according to 356 * the keys. 357 */ 358 const_iterator 359 begin() const _GLIBCXX_NOEXCEPT 360 { return _M_t.begin(); } 361 362 /** 363 * Returns a read/write iterator that points one past the last pair in 364 * the %multimap. Iteration is done in ascending order according to the 365 * keys. 366 */ 367 iterator 368 end() _GLIBCXX_NOEXCEPT 369 { return _M_t.end(); } 370 371 /** 372 * Returns a read-only (constant) iterator that points one past the last 373 * pair in the %multimap. Iteration is done in ascending order according 374 * to the keys. 375 */ 376 const_iterator 377 end() const _GLIBCXX_NOEXCEPT 378 { return _M_t.end(); } 379 380 /** 381 * Returns a read/write reverse iterator that points to the last pair in 382 * the %multimap. Iteration is done in descending order according to the 383 * keys. 384 */ 385 reverse_iterator 386 rbegin() _GLIBCXX_NOEXCEPT 387 { return _M_t.rbegin(); } 388 389 /** 390 * Returns a read-only (constant) reverse iterator that points to the 391 * last pair in the %multimap. Iteration is done in descending order 392 * according to the keys. 393 */ 394 const_reverse_iterator 395 rbegin() const _GLIBCXX_NOEXCEPT 396 { return _M_t.rbegin(); } 397 398 /** 399 * Returns a read/write reverse iterator that points to one before the 400 * first pair in the %multimap. Iteration is done in descending order 401 * according to the keys. 402 */ 403 reverse_iterator 404 rend() _GLIBCXX_NOEXCEPT 405 { return _M_t.rend(); } 406 407 /** 408 * Returns a read-only (constant) reverse iterator that points to one 409 * before the first pair in the %multimap. Iteration is done in 410 * descending order according to the keys. 411 */ 412 const_reverse_iterator 413 rend() const _GLIBCXX_NOEXCEPT 414 { return _M_t.rend(); } 415 416#if __cplusplus >= 201103L 417 /** 418 * Returns a read-only (constant) iterator that points to the first pair 419 * in the %multimap. Iteration is done in ascending order according to 420 * the keys. 421 */ 422 const_iterator 423 cbegin() const noexcept 424 { return _M_t.begin(); } 425 426 /** 427 * Returns a read-only (constant) iterator that points one past the last 428 * pair in the %multimap. Iteration is done in ascending order according 429 * to the keys. 430 */ 431 const_iterator 432 cend() const noexcept 433 { return _M_t.end(); } 434 435 /** 436 * Returns a read-only (constant) reverse iterator that points to the 437 * last pair in the %multimap. Iteration is done in descending order 438 * according to the keys. 439 */ 440 const_reverse_iterator 441 crbegin() const noexcept 442 { return _M_t.rbegin(); } 443 444 /** 445 * Returns a read-only (constant) reverse iterator that points to one 446 * before the first pair in the %multimap. Iteration is done in 447 * descending order according to the keys. 448 */ 449 const_reverse_iterator 450 crend() const noexcept 451 { return _M_t.rend(); } 452#endif 453 454 // capacity 455 /** Returns true if the %multimap is empty. */ 456 bool 457 empty() const _GLIBCXX_NOEXCEPT 458 { return _M_t.empty(); } 459 460 /** Returns the size of the %multimap. */ 461 size_type 462 size() const _GLIBCXX_NOEXCEPT 463 { return _M_t.size(); } 464 465 /** Returns the maximum size of the %multimap. */ 466 size_type 467 max_size() const _GLIBCXX_NOEXCEPT 468 { return _M_t.max_size(); } 469 470 // modifiers 471#if __cplusplus >= 201103L 472 /** 473 * @brief Build and insert a std::pair into the %multimap. 474 * 475 * @param __args Arguments used to generate a new pair instance (see 476 * std::piecewise_contruct for passing arguments to each 477 * part of the pair constructor). 478 * 479 * @return An iterator that points to the inserted (key,value) pair. 480 * 481 * This function builds and inserts a (key, value) %pair into the 482 * %multimap. 483 * Contrary to a std::map the %multimap does not rely on unique keys and 484 * thus multiple pairs with the same key can be inserted. 485 * 486 * Insertion requires logarithmic time. 487 */ 488 template<typename... _Args> 489 iterator 490 emplace(_Args&&... __args) 491 { return _M_t._M_emplace_equal(std::forward<_Args>(__args)...); } 492 493 /** 494 * @brief Builds and inserts a std::pair into the %multimap. 495 * 496 * @param __pos An iterator that serves as a hint as to where the pair 497 * should be inserted. 498 * @param __args Arguments used to generate a new pair instance (see 499 * std::piecewise_contruct for passing arguments to each 500 * part of the pair constructor). 501 * @return An iterator that points to the inserted (key,value) pair. 502 * 503 * This function inserts a (key, value) pair into the %multimap. 504 * Contrary to a std::map the %multimap does not rely on unique keys and 505 * thus multiple pairs with the same key can be inserted. 506 * Note that the first parameter is only a hint and can potentially 507 * improve the performance of the insertion process. A bad hint would 508 * cause no gains in efficiency. 509 * 510 * For more on @a hinting, see: 511 * http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html 512 * 513 * Insertion requires logarithmic time (if the hint is not taken). 514 */ 515 template<typename... _Args> 516 iterator 517 emplace_hint(const_iterator __pos, _Args&&... __args) 518 { 519 return _M_t._M_emplace_hint_equal(__pos, 520 std::forward<_Args>(__args)...); 521 } 522#endif 523 524 /** 525 * @brief Inserts a std::pair into the %multimap. 526 * @param __x Pair to be inserted (see std::make_pair for easy creation 527 * of pairs). 528 * @return An iterator that points to the inserted (key,value) pair. 529 * 530 * This function inserts a (key, value) pair into the %multimap. 531 * Contrary to a std::map the %multimap does not rely on unique keys and 532 * thus multiple pairs with the same key can be inserted. 533 * 534 * Insertion requires logarithmic time. 535 */ 536 iterator 537 insert(const value_type& __x) 538 { return _M_t._M_insert_equal(__x); } 539 540#if __cplusplus >= 201103L 541 template<typename _Pair, typename = typename 542 std::enable_if<std::is_constructible<value_type, 543 _Pair&&>::value>::type> 544 iterator 545 insert(_Pair&& __x) 546 { return _M_t._M_insert_equal(std::forward<_Pair>(__x)); } 547#endif 548 549 /** 550 * @brief Inserts a std::pair into the %multimap. 551 * @param __position An iterator that serves as a hint as to where the 552 * pair should be inserted. 553 * @param __x Pair to be inserted (see std::make_pair for easy creation 554 * of pairs). 555 * @return An iterator that points to the inserted (key,value) pair. 556 * 557 * This function inserts a (key, value) pair into the %multimap. 558 * Contrary to a std::map the %multimap does not rely on unique keys and 559 * thus multiple pairs with the same key can be inserted. 560 * Note that the first parameter is only a hint and can potentially 561 * improve the performance of the insertion process. A bad hint would 562 * cause no gains in efficiency. 563 * 564 * For more on @a hinting, see: 565 * http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html 566 * 567 * Insertion requires logarithmic time (if the hint is not taken). 568 */ 569 iterator 570#if __cplusplus >= 201103L 571 insert(const_iterator __position, const value_type& __x) 572#else 573 insert(iterator __position, const value_type& __x) 574#endif 575 { return _M_t._M_insert_equal_(__position, __x); } 576 577#if __cplusplus >= 201103L 578 template<typename _Pair, typename = typename 579 std::enable_if<std::is_constructible<value_type, 580 _Pair&&>::value>::type> 581 iterator 582 insert(const_iterator __position, _Pair&& __x) 583 { return _M_t._M_insert_equal_(__position, 584 std::forward<_Pair>(__x)); } 585#endif 586 587 /** 588 * @brief A template function that attempts to insert a range 589 * of elements. 590 * @param __first Iterator pointing to the start of the range to be 591 * inserted. 592 * @param __last Iterator pointing to the end of the range. 593 * 594 * Complexity similar to that of the range constructor. 595 */ 596 template<typename _InputIterator> 597 void 598 insert(_InputIterator __first, _InputIterator __last) 599 { _M_t._M_insert_equal(__first, __last); } 600 601#if __cplusplus >= 201103L 602 /** 603 * @brief Attempts to insert a list of std::pairs into the %multimap. 604 * @param __l A std::initializer_list<value_type> of pairs to be 605 * inserted. 606 * 607 * Complexity similar to that of the range constructor. 608 */ 609 void 610 insert(initializer_list<value_type> __l) 611 { this->insert(__l.begin(), __l.end()); } 612#endif 613 614#if __cplusplus >= 201103L 615 // _GLIBCXX_RESOLVE_LIB_DEFECTS 616 // DR 130. Associative erase should return an iterator. 617 /** 618 * @brief Erases an element from a %multimap. 619 * @param __position An iterator pointing to the element to be erased. 620 * @return An iterator pointing to the element immediately following 621 * @a position prior to the element being erased. If no such 622 * element exists, end() is returned. 623 * 624 * This function erases an element, pointed to by the given iterator, 625 * from a %multimap. Note that this function only erases the element, 626 * and that if the element is itself a pointer, the pointed-to memory is 627 * not touched in any way. Managing the pointer is the user's 628 * responsibility. 629 */ 630 iterator 631 erase(const_iterator __position) 632 { return _M_t.erase(__position); } 633 634 // LWG 2059. 635 _GLIBCXX_ABI_TAG_CXX11 636 iterator 637 erase(iterator __position) 638 { return _M_t.erase(__position); } 639#else 640 /** 641 * @brief Erases an element from a %multimap. 642 * @param __position An iterator pointing to the element to be erased. 643 * 644 * This function erases an element, pointed to by the given iterator, 645 * from a %multimap. Note that this function only erases the element, 646 * and that if the element is itself a pointer, the pointed-to memory is 647 * not touched in any way. Managing the pointer is the user's 648 * responsibility. 649 */ 650 void 651 erase(iterator __position) 652 { _M_t.erase(__position); } 653#endif 654 655 /** 656 * @brief Erases elements according to the provided key. 657 * @param __x Key of element to be erased. 658 * @return The number of elements erased. 659 * 660 * This function erases all elements located by the given key from a 661 * %multimap. 662 * Note that this function only erases the element, and that if 663 * the element is itself a pointer, the pointed-to memory is not touched 664 * in any way. Managing the pointer is the user's responsibility. 665 */ 666 size_type 667 erase(const key_type& __x) 668 { return _M_t.erase(__x); } 669 670#if __cplusplus >= 201103L 671 // _GLIBCXX_RESOLVE_LIB_DEFECTS 672 // DR 130. Associative erase should return an iterator. 673 /** 674 * @brief Erases a [first,last) range of elements from a %multimap. 675 * @param __first Iterator pointing to the start of the range to be 676 * erased. 677 * @param __last Iterator pointing to the end of the range to be 678 * erased . 679 * @return The iterator @a __last. 680 * 681 * This function erases a sequence of elements from a %multimap. 682 * Note that this function only erases the elements, and that if 683 * the elements themselves are pointers, the pointed-to memory is not 684 * touched in any way. Managing the pointer is the user's 685 * responsibility. 686 */ 687 iterator 688 erase(const_iterator __first, const_iterator __last) 689 { return _M_t.erase(__first, __last); } 690#else 691 // _GLIBCXX_RESOLVE_LIB_DEFECTS 692 // DR 130. Associative erase should return an iterator. 693 /** 694 * @brief Erases a [first,last) range of elements from a %multimap. 695 * @param __first Iterator pointing to the start of the range to be 696 * erased. 697 * @param __last Iterator pointing to the end of the range to 698 * be erased. 699 * 700 * This function erases a sequence of elements from a %multimap. 701 * Note that this function only erases the elements, and that if 702 * the elements themselves are pointers, the pointed-to memory is not 703 * touched in any way. Managing the pointer is the user's 704 * responsibility. 705 */ 706 void 707 erase(iterator __first, iterator __last) 708 { _M_t.erase(__first, __last); } 709#endif 710 711 /** 712 * @brief Swaps data with another %multimap. 713 * @param __x A %multimap of the same element and allocator types. 714 * 715 * This exchanges the elements between two multimaps in constant time. 716 * (It is only swapping a pointer, an integer, and an instance of 717 * the @c Compare type (which itself is often stateless and empty), so it 718 * should be quite fast.) 719 * Note that the global std::swap() function is specialized such that 720 * std::swap(m1,m2) will feed to this function. 721 */ 722 void 723 swap(multimap& __x) 724#if __cplusplus >= 201103L 725 noexcept(_Alloc_traits::_S_nothrow_swap()) 726#endif 727 { _M_t.swap(__x._M_t); } 728 729 /** 730 * Erases all elements in a %multimap. Note that this function only 731 * erases the elements, and that if the elements themselves are pointers, 732 * the pointed-to memory is not touched in any way. Managing the pointer 733 * is the user's responsibility. 734 */ 735 void 736 clear() _GLIBCXX_NOEXCEPT 737 { _M_t.clear(); } 738 739 // observers 740 /** 741 * Returns the key comparison object out of which the %multimap 742 * was constructed. 743 */ 744 key_compare 745 key_comp() const 746 { return _M_t.key_comp(); } 747 748 /** 749 * Returns a value comparison object, built from the key comparison 750 * object out of which the %multimap was constructed. 751 */ 752 value_compare 753 value_comp() const 754 { return value_compare(_M_t.key_comp()); } 755 756 // multimap operations 757 /** 758 * @brief Tries to locate an element in a %multimap. 759 * @param __x Key of (key, value) pair to be located. 760 * @return Iterator pointing to sought-after element, 761 * or end() if not found. 762 * 763 * This function takes a key and tries to locate the element with which 764 * the key matches. If successful the function returns an iterator 765 * pointing to the sought after %pair. If unsuccessful it returns the 766 * past-the-end ( @c end() ) iterator. 767 */ 768 iterator 769 find(const key_type& __x) 770 { return _M_t.find(__x); } 771 772 /** 773 * @brief Tries to locate an element in a %multimap. 774 * @param __x Key of (key, value) pair to be located. 775 * @return Read-only (constant) iterator pointing to sought-after 776 * element, or end() if not found. 777 * 778 * This function takes a key and tries to locate the element with which 779 * the key matches. If successful the function returns a constant 780 * iterator pointing to the sought after %pair. If unsuccessful it 781 * returns the past-the-end ( @c end() ) iterator. 782 */ 783 const_iterator 784 find(const key_type& __x) const 785 { return _M_t.find(__x); } 786 787 /** 788 * @brief Finds the number of elements with given key. 789 * @param __x Key of (key, value) pairs to be located. 790 * @return Number of elements with specified key. 791 */ 792 size_type 793 count(const key_type& __x) const 794 { return _M_t.count(__x); } 795 796 /** 797 * @brief Finds the beginning of a subsequence matching given key. 798 * @param __x Key of (key, value) pair to be located. 799 * @return Iterator pointing to first element equal to or greater 800 * than key, or end(). 801 * 802 * This function returns the first element of a subsequence of elements 803 * that matches the given key. If unsuccessful it returns an iterator 804 * pointing to the first element that has a greater value than given key 805 * or end() if no such element exists. 806 */ 807 iterator 808 lower_bound(const key_type& __x) 809 { return _M_t.lower_bound(__x); } 810 811 /** 812 * @brief Finds the beginning of a subsequence matching given key. 813 * @param __x Key of (key, value) pair to be located. 814 * @return Read-only (constant) iterator pointing to first element 815 * equal to or greater than key, or end(). 816 * 817 * This function returns the first element of a subsequence of 818 * elements that matches the given key. If unsuccessful the 819 * iterator will point to the next greatest element or, if no 820 * such greater element exists, to end(). 821 */ 822 const_iterator 823 lower_bound(const key_type& __x) const 824 { return _M_t.lower_bound(__x); } 825 826 /** 827 * @brief Finds the end of a subsequence matching given key. 828 * @param __x Key of (key, value) pair to be located. 829 * @return Iterator pointing to the first element 830 * greater than key, or end(). 831 */ 832 iterator 833 upper_bound(const key_type& __x) 834 { return _M_t.upper_bound(__x); } 835 836 /** 837 * @brief Finds the end of a subsequence matching given key. 838 * @param __x Key of (key, value) pair to be located. 839 * @return Read-only (constant) iterator pointing to first iterator 840 * greater than key, or end(). 841 */ 842 const_iterator 843 upper_bound(const key_type& __x) const 844 { return _M_t.upper_bound(__x); } 845 846 /** 847 * @brief Finds a subsequence matching given key. 848 * @param __x Key of (key, value) pairs to be located. 849 * @return Pair of iterators that possibly points to the subsequence 850 * matching given key. 851 * 852 * This function is equivalent to 853 * @code 854 * std::make_pair(c.lower_bound(val), 855 * c.upper_bound(val)) 856 * @endcode 857 * (but is faster than making the calls separately). 858 */ 859 std::pair<iterator, iterator> 860 equal_range(const key_type& __x) 861 { return _M_t.equal_range(__x); } 862 863 /** 864 * @brief Finds a subsequence matching given key. 865 * @param __x Key of (key, value) pairs to be located. 866 * @return Pair of read-only (constant) iterators that possibly points 867 * to the subsequence matching given key. 868 * 869 * This function is equivalent to 870 * @code 871 * std::make_pair(c.lower_bound(val), 872 * c.upper_bound(val)) 873 * @endcode 874 * (but is faster than making the calls separately). 875 */ 876 std::pair<const_iterator, const_iterator> 877 equal_range(const key_type& __x) const 878 { return _M_t.equal_range(__x); } 879 880 template<typename _K1, typename _T1, typename _C1, typename _A1> 881 friend bool 882 operator==(const multimap<_K1, _T1, _C1, _A1>&, 883 const multimap<_K1, _T1, _C1, _A1>&); 884 885 template<typename _K1, typename _T1, typename _C1, typename _A1> 886 friend bool 887 operator<(const multimap<_K1, _T1, _C1, _A1>&, 888 const multimap<_K1, _T1, _C1, _A1>&); 889 }; 890 891 /** 892 * @brief Multimap equality comparison. 893 * @param __x A %multimap. 894 * @param __y A %multimap of the same type as @a __x. 895 * @return True iff the size and elements of the maps are equal. 896 * 897 * This is an equivalence relation. It is linear in the size of the 898 * multimaps. Multimaps are considered equivalent if their sizes are equal, 899 * and if corresponding elements compare equal. 900 */ 901 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc> 902 inline bool 903 operator==(const multimap<_Key, _Tp, _Compare, _Alloc>& __x, 904 const multimap<_Key, _Tp, _Compare, _Alloc>& __y) 905 { return __x._M_t == __y._M_t; } 906 907 /** 908 * @brief Multimap ordering relation. 909 * @param __x A %multimap. 910 * @param __y A %multimap of the same type as @a __x. 911 * @return True iff @a x is lexicographically less than @a y. 912 * 913 * This is a total ordering relation. It is linear in the size of the 914 * multimaps. The elements must be comparable with @c <. 915 * 916 * See std::lexicographical_compare() for how the determination is made. 917 */ 918 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc> 919 inline bool 920 operator<(const multimap<_Key, _Tp, _Compare, _Alloc>& __x, 921 const multimap<_Key, _Tp, _Compare, _Alloc>& __y) 922 { return __x._M_t < __y._M_t; } 923 924 /// Based on operator== 925 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc> 926 inline bool 927 operator!=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x, 928 const multimap<_Key, _Tp, _Compare, _Alloc>& __y) 929 { return !(__x == __y); } 930 931 /// Based on operator< 932 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc> 933 inline bool 934 operator>(const multimap<_Key, _Tp, _Compare, _Alloc>& __x, 935 const multimap<_Key, _Tp, _Compare, _Alloc>& __y) 936 { return __y < __x; } 937 938 /// Based on operator< 939 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc> 940 inline bool 941 operator<=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x, 942 const multimap<_Key, _Tp, _Compare, _Alloc>& __y) 943 { return !(__y < __x); } 944 945 /// Based on operator< 946 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc> 947 inline bool 948 operator>=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x, 949 const multimap<_Key, _Tp, _Compare, _Alloc>& __y) 950 { return !(__x < __y); } 951 952 /// See std::multimap::swap(). 953 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc> 954 inline void 955 swap(multimap<_Key, _Tp, _Compare, _Alloc>& __x, 956 multimap<_Key, _Tp, _Compare, _Alloc>& __y) 957 { __x.swap(__y); } 958 959_GLIBCXX_END_NAMESPACE_CONTAINER 960} // namespace std 961 962#endif /* _STL_MULTIMAP_H */ 963