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