Lists将元素按链式储存在链表中。 与 向量(vector)相比, 它允许快速的插入和删除,但是随机访问却比较慢。
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 |
// List implementation -*- C++ -*- // Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library is free // software; you can redistribute it and/or modify it under the // terms of the GNU General Public License as published by the // Free Software Foundation; either version 2, or (at your option) // any later version. // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // You should have received a copy of the GNU General Public License along // with this library; see the file COPYING. If not, write to the Free // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, // USA. // As a special exception, you may use this file as part of a free software // library without restriction. Specifically, if other files instantiate // templates or use macros or inline functions from this file, or you compile // this file and link it with other files to produce an executable, this // file does not by itself cause the resulting executable to be covered by // the GNU General Public License. This exception does not however // invalidate any other reasons why the executable file might be covered by // the GNU General Public License. /* * * Copyright (c) 1994 * Hewlett-Packard Company * * Permission to use, copy, modify, distribute and sell this software * and its documentation for any purpose is hereby granted without fee, * provided that the above copyright notice appear in all copies and * that both that copyright notice and this permission notice appear * in supporting documentation. Hewlett-Packard Company makes no * representations about the suitability of this software for any * purpose. It is provided "as is" without express or implied warranty. * * * Copyright (c) 1996,1997 * Silicon Graphics Computer Systems, Inc. * * Permission to use, copy, modify, distribute and sell this software * and its documentation for any purpose is hereby granted without fee, * provided that the above copyright notice appear in all copies and * that both that copyright notice and this permission notice appear * in supporting documentation. Silicon Graphics makes no * representations about the suitability of this software for any * purpose. It is provided "as is" without express or implied warranty. */ /** @file stl_list.h * This is an internal header file, included by other library headers. * You should not attempt to use it directly. */ #ifndef _LIST_H #define _LIST_H 1 #include <bits/concept_check.h> namespace _GLIBCXX_STD { // Supporting structures are split into common and templated types; the // latter publicly inherits from the former in an effort to reduce code // duplication. This results in some "needless" static_cast'ing later on, // but it's all safe downcasting. /// @if maint Common part of a node in the %list. @endif struct _List_node_base { _List_node_base* _M_next; ///< Self-explanatory _List_node_base* _M_prev; ///< Self-explanatory static void swap(_List_node_base& __x, _List_node_base& __y); void transfer(_List_node_base * const __first, _List_node_base * const __last); void reverse(); void hook(_List_node_base * const __position); void unhook(); }; /// @if maint An actual node in the %list. @endif template<typename _Tp> struct _List_node : public _List_node_base { _Tp _M_data; ///< User's data. }; /** * @brief A list::iterator. * * @if maint * All the functions are op overloads. * @endif */ template<typename _Tp> struct _List_iterator { typedef _List_iterator<_Tp> _Self; typedef _List_node<_Tp> _Node; typedef ptrdiff_t difference_type; typedef bidirectional_iterator_tag iterator_category; typedef _Tp value_type; typedef _Tp* pointer; typedef _Tp& reference; _List_iterator() : _M_node() { } _List_iterator(_List_node_base* __x) : _M_node(__x) { } // Must downcast from List_node_base to _List_node to get to _M_data. reference operator*() const { return static_cast<_Node*>(_M_node)->_M_data; } pointer operator->() const { return &static_cast<_Node*>(_M_node)->_M_data; } _Self& operator++() { _M_node = _M_node->_M_next; return *this; } _Self operator++(int) { _Self __tmp = *this; _M_node = _M_node->_M_next; return __tmp; } _Self& operator--() { _M_node = _M_node->_M_prev; return *this; } _Self operator--(int) { _Self __tmp = *this; _M_node = _M_node->_M_prev; return __tmp; } bool operator==(const _Self& __x) const { return _M_node == __x._M_node; } bool operator!=(const _Self& __x) const { return _M_node != __x._M_node; } // The only member points to the %list element. _List_node_base* _M_node; }; /** * @brief A list::const_iterator. * * @if maint * All the functions are op overloads. * @endif */ template<typename _Tp> struct _List_const_iterator { typedef _List_const_iterator<_Tp> _Self; typedef const _List_node<_Tp> _Node; typedef _List_iterator<_Tp> iterator; typedef ptrdiff_t difference_type; typedef bidirectional_iterator_tag iterator_category; typedef _Tp value_type; typedef const _Tp* pointer; typedef const _Tp& reference; _List_const_iterator() : _M_node() { } _List_const_iterator(const _List_node_base* __x) : _M_node(__x) { } _List_const_iterator(const iterator& __x) : _M_node(__x._M_node) { } // Must downcast from List_node_base to _List_node to get to // _M_data. reference operator*() const { return static_cast<_Node*>(_M_node)->_M_data; } pointer operator->() const { return &static_cast<_Node*>(_M_node)->_M_data; } _Self& operator++() { _M_node = _M_node->_M_next; return *this; } _Self operator++(int) { _Self __tmp = *this; _M_node = _M_node->_M_next; return __tmp; } _Self& operator--() { _M_node = _M_node->_M_prev; return *this; } _Self operator--(int) { _Self __tmp = *this; _M_node = _M_node->_M_prev; return __tmp; } bool operator==(const _Self& __x) const { return _M_node == __x._M_node; } bool operator!=(const _Self& __x) const { return _M_node != __x._M_node; } // The only member points to the %list element. const _List_node_base* _M_node; }; template<typename _Val> inline bool operator==(const _List_iterator<_Val>& __x, const _List_const_iterator<_Val>& __y) { return __x._M_node == __y._M_node; } template<typename _Val> inline bool operator!=(const _List_iterator<_Val>& __x, const _List_const_iterator<_Val>& __y) { return __x._M_node != __y._M_node; } /** * @if maint * See bits/stl_deque.h's _Deque_base for an explanation. * @endif */ template<typename _Tp, typename _Alloc> class _List_base { protected: // NOTA BENE // The stored instance is not actually of "allocator_type"'s // type. Instead we rebind the type to // Allocator<List_node<Tp>>, which according to [20.1.5]/4 // should probably be the same. List_node<Tp> is not the same // size as Tp (it's two pointers larger), and specializations on // Tp may go unused because List_node<Tp> is being bound // instead. // // We put this to the test in the constructors and in // get_allocator, where we use conversions between // allocator_type and _Node_Alloc_type. The conversion is // required by table 32 in [20.1.5]. typedef typename _Alloc::template rebind<_List_node<_Tp> >::other _Node_Alloc_type; struct _List_impl : public _Node_Alloc_type { _List_node_base _M_node; _List_impl (const _Node_Alloc_type& __a) : _Node_Alloc_type(__a) { } }; _List_impl _M_impl; _List_node<_Tp>* _M_get_node() { return _M_impl._Node_Alloc_type::allocate(1); } void _M_put_node(_List_node<_Tp>* __p) { _M_impl._Node_Alloc_type::deallocate(__p, 1); } public: typedef _Alloc allocator_type; allocator_type get_allocator() const { return allocator_type(*static_cast<const _Node_Alloc_type*>(&this->_M_impl)); } _List_base(const allocator_type& __a) : _M_impl(__a) { _M_init(); } // This is what actually destroys the list. ~_List_base() { _M_clear(); } void _M_clear(); void _M_init() { this->_M_impl._M_node._M_next = &this->_M_impl._M_node; this->_M_impl._M_node._M_prev = &this->_M_impl._M_node; } }; /** * @brief A standard container with linear time access to elements, * and fixed time insertion/deletion at any point in the sequence. * * @ingroup Containers * @ingroup Sequences * * Meets the requirements of a <a href="tables.html#65">container</a>, a * <a href="tables.html#66">reversible container</a>, and a * <a href="tables.html#67">sequence</a>, including the * <a href="tables.html#68">optional sequence requirements</a> with the * %exception of @c at and @c operator[]. * * This is a @e doubly @e linked %list. Traversal up and down the * %list requires linear time, but adding and removing elements (or * @e nodes) is done in constant time, regardless of where the * change takes place. Unlike std::vector and std::deque, * random-access iterators are not provided, so subscripting ( @c * [] ) access is not allowed. For algorithms which only need * sequential access, this lack makes no difference. * * Also unlike the other standard containers, std::list provides * specialized algorithms %unique to linked lists, such as * splicing, sorting, and in-place reversal. * * @if maint * A couple points on memory allocation for list<Tp>: * * First, we never actually allocate a Tp, we allocate * List_node<Tp>'s and trust [20.1.5]/4 to DTRT. This is to ensure * that after elements from %list<X,Alloc1> are spliced into * %list<X,Alloc2>, destroying the memory of the second %list is a * valid operation, i.e., Alloc1 giveth and Alloc2 taketh away. * * Second, a %list conceptually represented as * @code * A <---> B <---> C <---> D * @endcode * is actually circular; a link exists between A and D. The %list * class holds (as its only data member) a private list::iterator * pointing to @e D, not to @e A! To get to the head of the %list, * we start at the tail and move forward by one. When this member * iterator's next/previous pointers refer to itself, the %list is * %empty. @endif */ template<typename _Tp, typename _Alloc = allocator<_Tp> > class list : protected _List_base<_Tp, _Alloc> { // concept requirements __glibcxx_class_requires(_Tp, _SGIAssignableConcept) typedef _List_base<_Tp, _Alloc> _Base; public: typedef _Tp value_type; typedef typename _Alloc::pointer pointer; typedef typename _Alloc::const_pointer const_pointer; typedef typename _Alloc::reference reference; typedef typename _Alloc::const_reference const_reference; typedef _List_iterator<_Tp> iterator; typedef _List_const_iterator<_Tp> const_iterator; typedef std::reverse_iterator<const_iterator> const_reverse_iterator; typedef std::reverse_iterator<iterator> reverse_iterator; typedef size_t size_type; typedef ptrdiff_t difference_type; typedef typename _Base::allocator_type allocator_type; protected: // Note that pointers-to-_Node's can be ctor-converted to // iterator types. typedef _List_node<_Tp> _Node; /** @if maint * One data member plus two memory-handling functions. If the * _Alloc type requires separate instances, then one of those * will also be included, accumulated from the topmost parent. * @endif */ using _Base::_M_impl; using _Base::_M_put_node; using _Base::_M_get_node; /** * @if maint * @param x An instance of user data. * * Allocates space for a new node and constructs a copy of @a x in it. * @endif */ _Node* _M_create_node(const value_type& __x) { _Node* __p = this->_M_get_node(); try { std::_Construct(&__p->_M_data, __x); } catch(...) { _M_put_node(__p); __throw_exception_again; } return __p; } /** * @if maint * Allocates space for a new node and default-constructs a new * instance of @c value_type in it. * @endif */ _Node* _M_create_node() { _Node* __p = this->_M_get_node(); try { std::_Construct(&__p->_M_data); } catch(...) { _M_put_node(__p); __throw_exception_again; } return __p; } public: // [23.2.2.1] construct/copy/destroy // (assign() and get_allocator() are also listed in this section) /** * @brief Default constructor creates no elements. */ explicit list(const allocator_type& __a = allocator_type()) : _Base(__a) { } /** * @brief Create a %list with copies of an exemplar element. * @param n The number of elements to initially create. * @param value An element to copy. * * This constructor fills the %list with @a n copies of @a value. */ list(size_type __n, const value_type& __value, const allocator_type& __a = allocator_type()) : _Base(__a) { this->insert(begin(), __n, __value); } /** * @brief Create a %list with default elements. * @param n The number of elements to initially create. * * This constructor fills the %list with @a n copies of a * default-constructed element. */ explicit list(size_type __n) : _Base(allocator_type()) { this->insert(begin(), __n, value_type()); } /** * @brief %List copy constructor. * @param x A %list of identical element and allocator types. * * The newly-created %list uses a copy of the allocation object used * by @a x. */ list(const list& __x) : _Base(__x.get_allocator()) { this->insert(begin(), __x.begin(), __x.end()); } /** * @brief Builds a %list from a range. * @param first An input iterator. * @param last An input iterator. * * Create a %list consisting of copies of the elements from * [@a first,@a last). This is linear in N (where N is * distance(@a first,@a last)). * * @if maint * We don't need any dispatching tricks here, because insert does all of * that anyway. * @endif */ template<typename _InputIterator> list(_InputIterator __first, _InputIterator __last, const allocator_type& __a = allocator_type()) : _Base(__a) { this->insert(begin(), __first, __last); } /** * No explicit dtor needed as the _Base dtor takes care of * things. The _Base dtor only erases the elements, and note * that if the elements themselves are pointers, the pointed-to * memory is not touched in any way. Managing the pointer is * the user's responsibilty. */ /** * @brief %List assignment operator. * @param x A %list of identical element and allocator types. * * All the elements of @a x are copied, but unlike the copy * constructor, the allocator object is not copied. */ list& operator=(const list& __x); /** * @brief Assigns a given value to a %list. * @param n Number of elements to be assigned. * @param val Value to be assigned. * * This function fills a %list with @a n copies of the given * value. Note that the assignment completely changes the %list * and that the resulting %list's size is the same as the number * of elements assigned. Old data may be lost. */ void assign(size_type __n, const value_type& __val) { _M_fill_assign(__n, __val); } /** * @brief Assigns a range to a %list. * @param first An input iterator. * @param last An input iterator. * * This function fills a %list with copies of the elements in the * range [@a first,@a last). * * Note that the assignment completely changes the %list and * that the resulting %list's size is the same as the number of * elements assigned. Old data may be lost. */ template<typename _InputIterator> void assign(_InputIterator __first, _InputIterator __last) { // Check whether it's an integral type. If so, it's not an iterator. typedef typename _Is_integer<_InputIterator>::_Integral _Integral; _M_assign_dispatch(__first, __last, _Integral()); } /// Get a copy of the memory allocation object. allocator_type get_allocator() const { return _Base::get_allocator(); } // iterators /** * Returns a read/write iterator that points to the first element in the * %list. Iteration is done in ordinary element order. */ iterator begin() { return this->_M_impl._M_node._M_next; } /** * Returns a read-only (constant) iterator that points to the * first element in the %list. Iteration is done in ordinary * element order. */ const_iterator begin() const { return this->_M_impl._M_node._M_next; } /** * Returns a read/write iterator that points one past the last * element in the %list. Iteration is done in ordinary element * order. */ iterator end() { return &this->_M_impl._M_node; } /** * Returns a read-only (constant) iterator that points one past * the last element in the %list. Iteration is done in ordinary * element order. */ const_iterator end() const { return &this->_M_impl._M_node; } /** * Returns a read/write reverse iterator that points to the last * element in the %list. Iteration is done in reverse element * order. */ reverse_iterator rbegin() { return reverse_iterator(end()); } /** * Returns a read-only (constant) reverse iterator that points to * the last element in the %list. Iteration is done in reverse * element order. */ const_reverse_iterator rbegin() const { return const_reverse_iterator(end()); } /** * Returns a read/write reverse iterator that points to one * before the first element in the %list. Iteration is done in * reverse element order. */ reverse_iterator rend() { return reverse_iterator(begin()); } /** * Returns a read-only (constant) reverse iterator that points to one * before the first element in the %list. Iteration is done in reverse * element order. */ const_reverse_iterator rend() const { return const_reverse_iterator(begin()); } // [23.2.2.2] capacity /** * Returns true if the %list is empty. (Thus begin() would equal * end().) */ bool empty() const { return this->_M_impl._M_node._M_next == &this->_M_impl._M_node; } /** Returns the number of elements in the %list. */ size_type size() const { return std::distance(begin(), end()); } /** Returns the size() of the largest possible %list. */ size_type max_size() const { return size_type(-1); } /** * @brief Resizes the %list to the specified number of elements. * @param new_size Number of elements the %list should contain. * @param x Data with which new elements should be populated. * * This function will %resize the %list to the specified number * of elements. If the number is smaller than the %list's * current size the %list is truncated, otherwise the %list is * extended and new elements are populated with given data. */ void resize(size_type __new_size, const value_type& __x); /** * @brief Resizes the %list to the specified number of elements. * @param new_size Number of elements the %list should contain. * * This function will resize the %list to the specified number of * elements. If the number is smaller than the %list's current * size the %list is truncated, otherwise the %list is extended * and new elements are default-constructed. */ void resize(size_type __new_size) { this->resize(__new_size, value_type()); } // element access /** * Returns a read/write reference to the data at the first * element of the %list. */ reference front() { return *begin(); } /** * Returns a read-only (constant) reference to the data at the first * element of the %list. */ const_reference front() const { return *begin(); } /** * Returns a read/write reference to the data at the last element * of the %list. */ reference back() { return *(--end()); } /** * Returns a read-only (constant) reference to the data at the last * element of the %list. */ const_reference back() const { return *(--end()); } // [23.2.2.3] modifiers /** * @brief Add data to the front of the %list. * @param x Data to be added. * * This is a typical stack operation. The function creates an * element at the front of the %list and assigns the given data * to it. Due to the nature of a %list this operation can be * done in constant time, and does not invalidate iterators and * references. */ void push_front(const value_type& __x) { this->_M_insert(begin(), __x); } /** * @brief Removes first element. * * This is a typical stack operation. It shrinks the %list by * one. Due to the nature of a %list this operation can be done * in constant time, and only invalidates iterators/references to * the element being removed. * * Note that no data is returned, and if the first element's data * is needed, it should be retrieved before pop_front() is * called. */ void pop_front() { this->_M_erase(begin()); } /** * @brief Add data to the end of the %list. * @param x Data to be added. * * This is a typical stack operation. The function creates an * element at the end of the %list and assigns the given data to * it. Due to the nature of a %list this operation can be done * in constant time, and does not invalidate iterators and * references. */ void push_back(const value_type& __x) { this->_M_insert(end(), __x); } /** * @brief Removes last element. * * This is a typical stack operation. It shrinks the %list by * one. Due to the nature of a %list this operation can be done * in constant time, and only invalidates iterators/references to * the element being removed. * * Note that no data is returned, and if the last element's data * is needed, it should be retrieved before pop_back() is called. */ void pop_back() { this->_M_erase(this->_M_impl._M_node._M_prev); } /** * @brief Inserts given value into %list before specified iterator. * @param position An iterator into the %list. * @param x Data to be inserted. * @return An iterator that points to the inserted data. * * This function will insert a copy of the given value before * the specified location. Due to the nature of a %list this * operation can be done in constant time, and does not * invalidate iterators and references. */ iterator insert(iterator __position, const value_type& __x); /** * @brief Inserts a number of copies of given data into the %list. * @param position An iterator into the %list. * @param n Number of elements to be inserted. * @param x Data to be inserted. * * This function will insert a specified number of copies of the * given data before the location specified by @a position. * * Due to the nature of a %list this operation can be done in * constant time, and does not invalidate iterators and * references. */ void insert(iterator __position, size_type __n, const value_type& __x) { _M_fill_insert(__position, __n, __x); } /** * @brief Inserts a range into the %list. * @param position An iterator into the %list. * @param first An input iterator. * @param last An input iterator. * * This function will insert copies of the data in the range [@a * first,@a last) into the %list before the location specified by * @a position. * * Due to the nature of a %list this operation can be done in * constant time, and does not invalidate iterators and * references. */ template<typename _InputIterator> void insert(iterator __position, _InputIterator __first, _InputIterator __last) { // Check whether it's an integral type. If so, it's not an iterator. typedef typename _Is_integer<_InputIterator>::_Integral _Integral; _M_insert_dispatch(__position, __first, __last, _Integral()); } /** * @brief Remove element at given position. * @param position Iterator pointing to element to be erased. * @return An iterator pointing to the next element (or end()). * * This function will erase the element at the given position and thus * shorten the %list by one. * * Due to the nature of a %list this operation can be done in * constant time, and only invalidates iterators/references to * the element being removed. The user is also cautioned that * this function only erases the element, and that if the element * is itself a pointer, the pointed-to memory is not touched in * any way. Managing the pointer is the user's responsibilty. */ iterator erase(iterator __position); /** * @brief Remove a range of elements. * @param first Iterator pointing to the first element to be erased. * @param last Iterator pointing to one past the last element to be * erased. * @return An iterator pointing to the element pointed to by @a last * prior to erasing (or end()). * * This function will erase the elements in the range @a * [first,last) and shorten the %list accordingly. * * Due to the nature of a %list this operation can be done in * constant time, and only invalidates iterators/references to * the element being removed. The user is also cautioned that * this function only erases the elements, and that if the * elements themselves are pointers, the pointed-to memory is not * touched in any way. Managing the pointer is the user's * responsibilty. */ iterator erase(iterator __first, iterator __last) { while (__first != __last) __first = erase(__first); return __last; } /** * @brief Swaps data with another %list. * @param x A %list of the same element and allocator types. * * This exchanges the elements between two lists in constant * time. Note that the global std::swap() function is * specialized such that std::swap(l1,l2) will feed to this * function. */ void swap(list& __x) { _List_node_base::swap(this->_M_impl._M_node,__x._M_impl._M_node); } /** * Erases all the elements. Note that this function only erases * the elements, and that if the elements themselves are * pointers, the pointed-to memory is not touched in any way. * Managing the pointer is the user's responsibilty. */ void clear() { _Base::_M_clear(); _Base::_M_init(); } // [23.2.2.4] list operations /** * @brief Insert contents of another %list. * @param position Iterator referencing the element to insert before. * @param x Source list. * * The elements of @a x are inserted in constant time in front of * the element referenced by @a position. @a x becomes an empty * list. */ void splice(iterator __position, list& __x) { if (!__x.empty()) this->_M_transfer(__position, __x.begin(), __x.end()); } /** * @brief Insert element from another %list. * @param position Iterator referencing the element to insert before. * @param x Source list. * @param i Iterator referencing the element to move. * * Removes the element in list @a x referenced by @a i and * inserts it into the current list before @a position. */ void splice(iterator __position, list&, iterator __i) { iterator __j = __i; ++__j; if (__position == __i || __position == __j) return; this->_M_transfer(__position, __i, __j); } /** * @brief Insert range from another %list. * @param position Iterator referencing the element to insert before. * @param x Source list. * @param first Iterator referencing the start of range in x. * @param last Iterator referencing the end of range in x. * * Removes elements in the range [first,last) and inserts them * before @a position in constant time. * * Undefined if @a position is in [first,last). */ void splice(iterator __position, list&, iterator __first, iterator __last) { if (__first != __last) this->_M_transfer(__position, __first, __last); } /** * @brief Remove all elements equal to value. * @param value The value to remove. * * Removes every element in the list equal to @a value. * Remaining elements stay in list order. Note that this * function only erases the elements, and that if the elements * themselves are pointers, the pointed-to memory is not * touched in any way. Managing the pointer is the user's * responsibilty. */ void remove(const _Tp& __value); /** * @brief Remove all elements satisfying a predicate. * @param Predicate Unary predicate function or object. * * Removes every element in the list for which the predicate * returns true. Remaining elements stay in list order. Note * that this function only erases the elements, and that if the * elements themselves are pointers, the pointed-to memory is * not touched in any way. Managing the pointer is the user's * responsibilty. */ template<typename _Predicate> void remove_if(_Predicate); /** * @brief Remove consecutive duplicate elements. * * For each consecutive set of elements with the same value, * remove all but the first one. Remaining elements stay in * list order. Note that this function only erases the * elements, and that if the elements themselves are pointers, * the pointed-to memory is not touched in any way. Managing * the pointer is the user's responsibilty. */ void unique(); /** * @brief Remove consecutive elements satisfying a predicate. * @param BinaryPredicate Binary predicate function or object. * * For each consecutive set of elements [first,last) that * satisfy predicate(first,i) where i is an iterator in * [first,last), remove all but the first one. Remaining * elements stay in list order. Note that this function only * erases the elements, and that if the elements themselves are * pointers, the pointed-to memory is not touched in any way. * Managing the pointer is the user's responsibilty. */ template<typename _BinaryPredicate> void unique(_BinaryPredicate); /** * @brief Merge sorted lists. * @param x Sorted list to merge. * * Assumes that both @a x and this list are sorted according to * operator<(). Merges elements of @a x into this list in * sorted order, leaving @a x empty when complete. Elements in * this list precede elements in @a x that are equal. */ void merge(list& __x); /** * @brief Merge sorted lists according to comparison function. * @param x Sorted list to merge. * @param StrictWeakOrdering Comparison function definining * sort order. * * Assumes that both @a x and this list are sorted according to * StrictWeakOrdering. Merges elements of @a x into this list * in sorted order, leaving @a x empty when complete. Elements * in this list precede elements in @a x that are equivalent * according to StrictWeakOrdering(). */ template<typename _StrictWeakOrdering> void merge(list&, _StrictWeakOrdering); /** * @brief Reverse the elements in list. * * Reverse the order of elements in the list in linear time. */ void reverse() { this->_M_impl._M_node.reverse(); } /** * @brief Sort the elements. * * Sorts the elements of this list in NlogN time. Equivalent * elements remain in list order. */ void sort(); /** * @brief Sort the elements according to comparison function. * * Sorts the elements of this list in NlogN time. Equivalent * elements remain in list order. */ template<typename _StrictWeakOrdering> void sort(_StrictWeakOrdering); protected: // Internal assign functions follow. // Called by the range assign to implement [23.1.1]/9 template<typename _Integer> void _M_assign_dispatch(_Integer __n, _Integer __val, __true_type) { _M_fill_assign(static_cast<size_type>(__n), static_cast<value_type>(__val)); } // Called by the range assign to implement [23.1.1]/9 template<typename _InputIterator> void _M_assign_dispatch(_InputIterator __first, _InputIterator __last, __false_type); // Called by assign(n,t), and the range assign when it turns out // to be the same thing. void _M_fill_assign(size_type __n, const value_type& __val); // Internal insert functions follow. // Called by the range insert to implement [23.1.1]/9 template<typename _Integer> void _M_insert_dispatch(iterator __pos, _Integer __n, _Integer __x, __true_type) { _M_fill_insert(__pos, static_cast<size_type>(__n), static_cast<value_type>(__x)); } // Called by the range insert to implement [23.1.1]/9 template<typename _InputIterator> void _M_insert_dispatch(iterator __pos, _InputIterator __first, _InputIterator __last, __false_type) { for ( ; __first != __last; ++__first) _M_insert(__pos, *__first); } // Called by insert(p,n,x), and the range insert when it turns out // to be the same thing. void _M_fill_insert(iterator __pos, size_type __n, const value_type& __x) { for ( ; __n > 0; --__n) _M_insert(__pos, __x); } // Moves the elements from [first,last) before position. void _M_transfer(iterator __position, iterator __first, iterator __last) { __position._M_node->transfer(__first._M_node,__last._M_node); } // Inserts new element at position given and with value given. void _M_insert(iterator __position, const value_type& __x) { _Node* __tmp = _M_create_node(__x); __tmp->hook(__position._M_node); } // Erases element at position given. void _M_erase(iterator __position) { __position._M_node->unhook(); _Node* __n = static_cast<_Node*>(__position._M_node); std::_Destroy(&__n->_M_data); _M_put_node(__n); } }; /** * @brief List equality comparison. * @param x A %list. * @param y A %list of the same type as @a x. * @return True iff the size and elements of the lists are equal. * * This is an equivalence relation. It is linear in the size of * the lists. Lists are considered equivalent if their sizes are * equal, and if corresponding elements compare equal. */ template<typename _Tp, typename _Alloc> inline bool operator==(const list<_Tp,_Alloc>& __x, const list<_Tp,_Alloc>& __y) { typedef typename list<_Tp,_Alloc>::const_iterator const_iterator; const_iterator __end1 = __x.end(); const_iterator __end2 = __y.end(); const_iterator __i1 = __x.begin(); const_iterator __i2 = __y.begin(); while (__i1 != __end1 && __i2 != __end2 && *__i1 == *__i2) { ++__i1; ++__i2; } return __i1 == __end1 && __i2 == __end2; } /** * @brief List ordering relation. * @param x A %list. * @param y A %list of the same type as @a x. * @return True iff @a x is lexicographically less than @a y. * * This is a total ordering relation. It is linear in the size of the * lists. The elements must be comparable with @c <. * * See std::lexicographical_compare() for how the determination is made. */ template<typename _Tp, typename _Alloc> inline bool operator<(const list<_Tp,_Alloc>& __x, const list<_Tp,_Alloc>& __y) { return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end()); } /// Based on operator== template<typename _Tp, typename _Alloc> inline bool operator!=(const list<_Tp,_Alloc>& __x, const list<_Tp,_Alloc>& __y) { return !(__x == __y); } /// Based on operator< template<typename _Tp, typename _Alloc> inline bool operator>(const list<_Tp,_Alloc>& __x, const list<_Tp,_Alloc>& __y) { return __y < __x; } /// Based on operator< template<typename _Tp, typename _Alloc> inline bool operator<=(const list<_Tp,_Alloc>& __x, const list<_Tp,_Alloc>& __y) { return !(__y < __x); } /// Based on operator< template<typename _Tp, typename _Alloc> inline bool operator>=(const list<_Tp,_Alloc>& __x, const list<_Tp,_Alloc>& __y) { return !(__x < __y); } /// See std::list::swap(). template<typename _Tp, typename _Alloc> inline void swap(list<_Tp, _Alloc>& __x, list<_Tp, _Alloc>& __y) { __x.swap(__y); } } // namespace std #endif /* _LIST_H */ |