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。
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// 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 */ |