stl_tree.h
stl_tree.h G++ 2.91.57,cygnus\cygwin-b20\include\g++\stl_tree.h 完整列表 /* * * 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. * * * 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. * * */ /* NOTE: This is an internal header file, included by other STL headers. * You should not attempt to use it directly. */ #ifndef __SGI_STL_INTERNAL_TREE_H #define __SGI_STL_INTERNAL_TREE_H /* 本檔實作Red-black tree(紅-黑樹)class,用以實作 STL 關聯式容器(如set, multiset, map, multimap)。所用之insertion 和deletion 演算法係以 Cormen, Leiserson 和 Rivest 所著之 Introduction to Algorithms (MIT Press, 1990) 一書為基礎,唯以下兩點不同: (1) header 不僅指向 root,也指向紅黑樹的最左節點,以便實作出常數時間之 begin();並且也指向紅黑樹的最右節點,以便set 相關泛型演算法(如set_union 等等)有線性時間之表現。 (2) 當一個即將被刪除之節點擁有兩個子節點時,它的successor node is relinked into its place, rather than copied, 如此一來唯一失效(invalidated)的迭代器就只是那些referring to the deleted node. */ #include <stl_algobase.h> #include <stl_alloc.h> #include <stl_construct.h> #include <stl_function.h> __STL_BEGIN_NAMESPACE typedef bool __rb_tree_color_type; const __rb_tree_color_type __rb_tree_red = false; // 紅色為 0 const __rb_tree_color_type __rb_tree_black = true; // 黑色為 1 struct __rb_tree_node_base { typedef __rb_tree_color_type color_type; typedef __rb_tree_node_base* base_ptr; color_type color; // 節點顏色,非紅即黑。 base_ptr parent; // RB 樹的許多操作,必須知道父節點。 base_ptr left; // 指向左節點。 base_ptr right; // 指向右節點。 static base_ptr minimum(base_ptr x) { while (x->left != 0) x = x->left; // 一直向左走,就會找到最小值, return x; // 這是二元搜尋樹的特性。 } static base_ptr maximum(base_ptr x) { while (x->right != 0) x = x->right; // 一直向右走,就會找到最大值, return x; // 這是二元搜尋樹的特性。 } }; template <class Value> struct __rb_tree_node : public __rb_tree_node_base { typedef __rb_tree_node<Value>* link_type; Value value_field; // 節點實值 }; struct __rb_tree_base_iterator { typedef __rb_tree_node_base::base_ptr base_ptr; typedef bidirectional_iterator_tag iterator_category; typedef ptrdiff_t difference_type; base_ptr node; // 它用來與容器之間產生一個連結關係(make a reference) // 以下其實可實作於 operator++ 內,因為再無他處會呼叫此函式了。 void increment() { if (node->right != 0) { // 如果有右子節點。狀況(1) node = node->right; // 就向右走 while (node->left != 0) // 然後一直往左子樹走到底 node = node->left; // 即是解答 } else { // 沒有右子節點。狀況(2) base_ptr y = node->parent; // 找出父節點 while (node == y->right) { // 如果現行節點本身是個右子節點, node = y; // 就一直上溯,直到「不為右子節點」止。 y = y->parent; } if (node->right != y) // 「若此時的右子節點不等於此時的父節點」。 node = y; // 狀況(3) 此時的父節點即為解答。 // 否則此時的node 為解答。狀況(4) } // 注意,以上判斷「若此時的右子節點不等於此時的父節點」,是為了應付一種 // 特殊情況:我們欲尋找根節點的下一節點,而恰巧根節點無右子節點。 // 當然,以上特殊作法必須配合 RB-tree 根節點與特殊之header 之間的 // 特殊關係。 } // 以下其實可實作於 operator-- 內,因為再無他處會呼叫此函式了。 void decrement() { if (node->color == __rb_tree_red && // 如果是紅節點,且 node->parent->parent == node) // 父節點的父節點等於自己, node = node->right; // 狀況(1) 右子節點即為解答。 // 以上情況發生於node為header時(亦即 node 為 end() 時)。 // 注意,header 之右子節點即 mostright,指向整棵樹的 max 節點。 else if (node->left != 0) { // 如果有左子節點。狀況(2) base_ptr y = node->left; // 令y指向左子節點 while (y->right != 0) // 當y有右子節點時 y = y->right; // 一直往右子節點走到底 node = y; // 最後即為答案 } else { // 既非根節點,亦無左子節點。 base_ptr y = node->parent; // 狀況(3) 找出父節點 while (node == y->left) { // 當現行節點身為左子節點 node = y; // 一直交替往上走,直到現行節點 y = y->parent; // 不為左子節點 } node = y; // 此時之父節點即為答案 } } }; template <class Value, class Ref, class Ptr> struct __rb_tree_iterator : public __rb_tree_base_iterator { typedef Value value_type; typedef Ref reference; typedef Ptr pointer; typedef __rb_tree_iterator<Value, Value&, Value*> iterator; typedef __rb_tree_iterator<Value, const Value&, const Value*> const_iterator; typedef __rb_tree_iterator<Value, Ref, Ptr> self; typedef __rb_tree_node<Value>* link_type; __rb_tree_iterator() {} __rb_tree_iterator(link_type x) { node = x; } __rb_tree_iterator(const iterator& it) { node = it.node; } reference operator*() const { return link_type(node)->value_field; } #ifndef __SGI_STL_NO_ARROW_OPERATOR pointer operator->() const { return &(operator*()); } #endif /* __SGI_STL_NO_ARROW_OPERATOR */ self& operator++() { increment(); return *this; } self operator++(int) { self tmp = *this; increment(); return tmp; } self& operator--() { decrement(); return *this; } self operator--(int) { self tmp = *this; decrement(); return tmp; } }; inline bool operator==(const __rb_tree_base_iterator& x, const __rb_tree_base_iterator& y) { return x.node == y.node; // 兩個迭代器相等,意指其所指的節點相等。 } inline bool operator!=(const __rb_tree_base_iterator& x, const __rb_tree_base_iterator& y) { return x.node != y.node; // 兩個迭代器不等,意指其所指的節點不等。 } #ifndef __STL_CLASS_PARTIAL_SPECIALIZATION inline bidirectional_iterator_tag iterator_category(const __rb_tree_base_iterator&) { return bidirectional_iterator_tag(); } inline __rb_tree_base_iterator::difference_type* distance_type(const __rb_tree_base_iterator&) { return (__rb_tree_base_iterator::difference_type*) 0; } template <class Value, class Ref, class Ptr> inline Value* value_type(const __rb_tree_iterator<Value, Ref, Ptr>&) { return (Value*) 0; } #endif /* __STL_CLASS_PARTIAL_SPECIALIZATION */ // 以下都是全域函式:__rb_tree_rotate_left(), __rb_tree_rotate_right(), // __rb_tree_rebalance(), __rb_tree_rebalance_for_erase() // 新節點必為紅節點。如果安插處之父節點亦為紅節點,就違反紅黑樹規則,此時必須 // 做樹形旋轉(及顏色改變,在程式它處)。 inline void __rb_tree_rotate_left(__rb_tree_node_base* x, __rb_tree_node_base*& root) { // x 為旋轉點 __rb_tree_node_base* y = x->right; // 令y 為旋轉點的右子節點 x->right = y->left; if (y->left !=0) y->left->parent = x; // 別忘了回馬槍設定父節點 y->parent = x->parent; // 令 y 完全頂替 x 的地位(必須將 x 對其父節點的關係完全接收過來) if (x == root) // x 為根節點 root = y; else if (x == x->parent->left) // x 為其父節點的左子節點 x->parent->left = y; else // x 為其父節點的右子節點 x->parent->right = y; y->left = x; x->parent = y; } // 新節點必為紅節點。如果安插處之父節點亦為紅節點,就違反紅黑樹規則,此時必須 // 做樹形旋轉(及顏色改變,在程式它處)。 inline void __rb_tree_rotate_right(__rb_tree_node_base* x, __rb_tree_node_base*& root) { // x 為旋轉點 __rb_tree_node_base* y = x->left; // y 為旋轉點的左子節點 x->left = y->right; if (y->right != 0) y->right->parent = x; // 別忘了回馬槍設定父節點 y->parent = x->parent; // 令 y 完全頂替 x 的地位(必須將 x 對其父節點的關係完全接收過來) if (x == root) // x 為根節點 root = y; else if (x == x->parent->right) // x 為其父節點的右子節點 x->parent->right = y; else // x 為其父節點的左子節點 x->parent->left = y; y->right = x; x->parent = y; } // 重新令樹形平衡(改變顏色及旋轉樹形) // 參數一為新增節點,參數二為 root inline void __rb_tree_rebalance(__rb_tree_node_base* x, __rb_tree_node_base*& root) { x->color = __rb_tree_red; // 新節點必為紅 while (x != root && x->parent->color == __rb_tree_red) { // 父節點為紅 if (x->parent == x->parent->parent->left) { // 父節點為祖父節點之左子節點 __rb_tree_node_base* y = x->parent->parent->right; // 令y 為伯父節點 if (y && y->color == __rb_tree_red) { // 伯父節點存在,且為紅 x->parent->color = __rb_tree_black; // 更改父節點為黑 y->color = __rb_tree_black; // 更改伯父節點為黑 x->parent->parent->color = __rb_tree_red; // 更改祖父節點為紅 x = x->parent->parent; } else { // 無伯父節點,或伯父節點為黑 if (x == x->parent->right) { // 如果新節點為父節點之右子節點 x = x->parent; __rb_tree_rotate_left(x, root); // 第一參數為左旋點 } x->parent->color = __rb_tree_black; // 改變顏色 x->parent->parent->color = __rb_tree_red; __rb_tree_rotate_right(x->parent->parent, root); // 第一參數為右旋點 } } else { // 父節點為祖父節點之右子節點 __rb_tree_node_base* y = x->parent->parent->left; // 令y 為伯父節點 if (y && y->color == __rb_tree_red) { // 有伯父節點,且為紅 x->parent->color = __rb_tree_black; // 更改父節點為黑 y->color = __rb_tree_black; // 更改伯父節點為黑 x->parent->parent->color = __rb_tree_red; // 更改祖父節點為紅 x = x->parent->parent; // 準備繼續往上層檢查... } else { // 無伯父節點,或伯父節點為黑 if (x == x->parent->left) { // 如果新節點為父節點之左子節點 x = x->parent; __rb_tree_rotate_right(x, root); // 第一參數為右旋點 } x->parent->color = __rb_tree_black; // 改變顏色 x->parent->parent->color = __rb_tree_red; __rb_tree_rotate_left(x->parent->parent, root); // 第一參數為左旋點 } } } // while 結束 root->color = __rb_tree_black; // 根節點永遠為黑 } inline __rb_tree_node_base* __rb_tree_rebalance_for_erase(__rb_tree_node_base* z, __rb_tree_node_base*& root, __rb_tree_node_base*& leftmost, __rb_tree_node_base*& rightmost) { __rb_tree_node_base* y = z; __rb_tree_node_base* x = 0; __rb_tree_node_base* x_parent = 0; if (y->left == 0) // z has at most one non-null child. y == z. x = y->right; // x might be null. else if (y->right == 0) // z has exactly one non-null child. y == z. x = y->left; // x is not null. else { // z has two non-null children. Set y to y = y->right; // z's successor. x might be null. while (y->left != 0) y = y->left; x = y->right; } if (y != z) { // relink y in place of z. y is z's successor z->left->parent = y; y->left = z->left; if (y != z->right) { x_parent = y->parent; if (x) x->parent = y->parent; y->parent->left = x; // y must be a left child y->right = z->right; z->right->parent = y; } else x_parent = y; if (root == z) root = y; else if (z->parent->left == z) z->parent->left = y; else z->parent->right = y; y->parent = z->parent; __STD::swap(y->color, z->color); y = z; // y now points to node to be actually deleted } else { // y == z x_parent = y->parent; if (x) x->parent = y->parent; if (root == z) root = x; else if (z->parent->left == z) z->parent->left = x; else z->parent->right = x; if (leftmost == z) if (z->right == 0) // z->left must be null also leftmost = z->parent; // makes leftmost == header if z == root else leftmost = __rb_tree_node_base::minimum(x); if (rightmost == z) if (z->left == 0) // z->right must be null also rightmost = z->parent; // makes rightmost == header if z == root else // x == z->left rightmost = __rb_tree_node_base::maximum(x); } if (y->color != __rb_tree_red) { while (x != root && (x == 0 || x->color == __rb_tree_black)) if (x == x_parent->left) { __rb_tree_node_base* w = x_parent->right; if (w->color == __rb_tree_red) { w->color = __rb_tree_black; x_parent->color = __rb_tree_red; __rb_tree_rotate_left(x_parent, root); w = x_parent->right; } if ((w->left == 0 || w->left->color == __rb_tree_black) && (w->right == 0 || w->right->color == __rb_tree_black)) { w->color = __rb_tree_red; x = x_parent; x_parent = x_parent->parent; } else { if (w->right == 0 || w->right->color == __rb_tree_black) { if (w->left) w->left->color = __rb_tree_black; w->color = __rb_tree_red; __rb_tree_rotate_right(w, root); w = x_parent->right; } w->color = x_parent->color; x_parent->color = __rb_tree_black; if (w->right) w->right->color = __rb_tree_black; __rb_tree_rotate_left(x_parent, root); break; } } else { // same as above, with right <-> left. __rb_tree_node_base* w = x_parent->left; if (w->color == __rb_tree_red) { w->color = __rb_tree_black; x_parent->color = __rb_tree_red; __rb_tree_rotate_right(x_parent, root); w = x_parent->left; } if ((w->right == 0 || w->right->color == __rb_tree_black) && (w->left == 0 || w->left->color == __rb_tree_black)) { w->color = __rb_tree_red; x = x_parent; x_parent = x_parent->parent; } else { if (w->left == 0 || w->left->color == __rb_tree_black) { if (w->right) w->right->color = __rb_tree_black; w->color = __rb_tree_red; __rb_tree_rotate_left(w, root); w = x_parent->left; } w->color = x_parent->color; x_parent->color = __rb_tree_black; if (w->left) w->left->color = __rb_tree_black; __rb_tree_rotate_right(x_parent, root); break; } } if (x) x->color = __rb_tree_black; } return y; } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc = alloc> class rb_tree { protected: typedef void* void_pointer; typedef __rb_tree_node_base* base_ptr; typedef __rb_tree_node<Value> rb_tree_node; typedef simple_alloc<rb_tree_node, Alloc> rb_tree_node_allocator; typedef __rb_tree_color_type color_type; public: // 注意,沒有定義 iterator(喔,不,定義在後面) typedef Key key_type; typedef Value value_type; typedef value_type* pointer; typedef const value_type* const_pointer; typedef value_type& reference; typedef const value_type& const_reference; typedef rb_tree_node* link_type; typedef size_t size_type; typedef ptrdiff_t difference_type; protected: link_type get_node() { return rb_tree_node_allocator::allocate(); } void put_node(link_type p) { rb_tree_node_allocator::deallocate(p); } link_type create_node(const value_type& x) { link_type tmp = get_node(); // 配置空間 __STL_TRY { construct(&tmp->value_field, x); // 建構內容 } __STL_UNWIND(put_node(tmp)); return tmp; } link_type clone_node(link_type x) { // 複製一個節點(的值和色) link_type tmp = create_node(x->value_field); tmp->color = x->color; tmp->left = 0; tmp->right = 0; return tmp; } void destroy_node(link_type p) { destroy(&p->value_field); // 解構內容 put_node(p); // 釋還記憶體 } protected: // RB-tree 只以三筆資料表現。 size_type node_count; // 追蹤記錄樹的大小(節點數量) link_type header; Compare key_compare; // 節點間的鍵值大小比較準則。應該會是個 function object。 // 以下三個函式用來方便取得 header 的成員 link_type& root() const { return (link_type&) header->parent; } link_type& leftmost() const { return (link_type&) header->left; } link_type& rightmost() const { return (link_type&) header->right; } // 以下六個函式用來方便取得節點 x 的成員 static link_type& left(link_type x) { return (link_type&)(x->left); } static link_type& right(link_type x) { return (link_type&)(x->right); } static link_type& parent(link_type x) { return (link_type&)(x->parent); } static reference value(link_type x) { return x->value_field; } static const Key& key(link_type x) { return KeyOfValue()(value(x)); } static color_type& color(link_type x) { return (color_type&)(x->color); } // 以下六個函式用來方便取得節點 x 的成員 static link_type& left(base_ptr x) { return (link_type&)(x->left); } static link_type& right(base_ptr x) { return (link_type&)(x->right); } static link_type& parent(base_ptr x) { return (link_type&)(x->parent); } static reference value(base_ptr x) { return ((link_type)x)->value_field; } static const Key& key(base_ptr x) { return KeyOfValue()(value(link_type(x)));} static color_type& color(base_ptr x) { return (color_type&)(link_type(x)->color); } // 求取極大值和極小值。node class 有實作此功能,交給它們完成即可。 static link_type minimum(link_type x) { return (link_type) __rb_tree_node_base::minimum(x); } static link_type maximum(link_type x) { return (link_type) __rb_tree_node_base::maximum(x); } public: typedef __rb_tree_iterator<value_type, reference, pointer> iterator; typedef __rb_tree_iterator<value_type, const_reference, const_pointer> const_iterator; #ifdef __STL_CLASS_PARTIAL_SPECIALIZATION typedef reverse_iterator<const_iterator> const_reverse_iterator; typedef reverse_iterator<iterator> reverse_iterator; #else /* __STL_CLASS_PARTIAL_SPECIALIZATION */ typedef reverse_bidirectional_iterator<iterator, value_type, reference, difference_type> reverse_iterator; typedef reverse_bidirectional_iterator<const_iterator, value_type, const_reference, difference_type> const_reverse_iterator; #endif /* __STL_CLASS_PARTIAL_SPECIALIZATION */ private: iterator __insert(base_ptr x, base_ptr y, const value_type& v); link_type __copy(link_type x, link_type p); void __erase(link_type x); void init() { header = get_node(); // 產生一個節點空間,令 header 指向它 color(header) = __rb_tree_red; // 令 header 為紅色,用來區分 header // 和 root(在 iterator.operator++ 中) root() = 0; leftmost() = header; // 令 header 的左子節點為自己。 rightmost() = header; // 令 header 的右子節點為自己。 } public: // allocation/deallocation rb_tree(const Compare& comp = Compare()) : node_count(0), key_compare(comp) { init(); } // 以另一個 rb_tree 物件 x 為初值 rb_tree(const rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& x) : node_count(0), key_compare(x.key_compare) { header = get_node(); // 產生一個節點空間,令 header 指向它 color(header) = __rb_tree_red; // 令 header 為紅色 if (x.root() == 0) { // 如果 x 是個空白樹 root() = 0; leftmost() = header; // 令 header 的左子節點為自己。 rightmost() = header; // 令 header 的右子節點為自己。 } else { // x 不是一個空白樹 __STL_TRY { root() = __copy(x.root(), header); // ??? } __STL_UNWIND(put_node(header)); leftmost() = minimum(root()); // 令 header 的左子節點為最小節點 rightmost() = maximum(root()); // 令 header 的右子節點為最大節點 } node_count = x.node_count; } ~rb_tree() { clear(); put_node(header); } rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& operator=(const rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& x); public: // accessors: Compare key_comp() const { return key_compare; } iterator begin() { return leftmost(); } // RB 樹的起頭為最左(最小)節點處 const_iterator begin() const { return leftmost(); } iterator end() { return header; } // RB 樹的終點為 header所指處 const_iterator end() const { return header; } reverse_iterator rbegin() { return reverse_iterator(end()); } const_reverse_iterator rbegin() const { return const_reverse_iterator(end()); } reverse_iterator rend() { return reverse_iterator(begin()); } const_reverse_iterator rend() const { return const_reverse_iterator(begin()); } bool empty() const { return node_count == 0; } size_type size() const { return node_count; } size_type max_size() const { return size_type(-1); } void swap(rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& t) { // RB-tree 只以三個資料成員表現。所以互換兩個 RB-trees時, // 只需將這三個成員互換即可。 __STD::swap(header, t.header); __STD::swap(node_count, t.node_count); __STD::swap(key_compare, t.key_compare); } public: // insert/erase // 將 x 安插到 RB-tree 中(保持節點值獨一無二)。 pair<iterator,bool> insert_unique(const value_type& x); // 將 x 安插到 RB-tree 中(允許節點值重複)。 iterator insert_equal(const value_type& x); iterator insert_unique(iterator position, const value_type& x); iterator insert_equal(iterator position, const value_type& x); #ifdef __STL_MEMBER_TEMPLATES template <class InputIterator> void insert_unique(InputIterator first, InputIterator last); template <class InputIterator> void insert_equal(InputIterator first, InputIterator last); #else /* __STL_MEMBER_TEMPLATES */ void insert_unique(const_iterator first, const_iterator last); void insert_unique(const value_type* first, const value_type* last); void insert_equal(const_iterator first, const_iterator last); void insert_equal(const value_type* first, const value_type* last); #endif /* __STL_MEMBER_TEMPLATES */ void erase(iterator position); size_type erase(const key_type& x); void erase(iterator first, iterator last); void erase(const key_type* first, const key_type* last); void clear() { if (node_count != 0) { __erase(root()); leftmost() = header; root() = 0; rightmost() = header; node_count = 0; } } public: // 集合(set)的各種操作行為: iterator find(const key_type& x); const_iterator find(const key_type& x) const; size_type count(const key_type& x) const; iterator lower_bound(const key_type& x); const_iterator lower_bound(const key_type& x) const; iterator upper_bound(const key_type& x); const_iterator upper_bound(const key_type& x) const; pair<iterator,iterator> equal_range(const key_type& x); pair<const_iterator, const_iterator> equal_range(const key_type& x) const; public: // Debugging. bool __rb_verify() const; }; template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> inline bool operator==(const rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& x, const rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& y) { return x.size() == y.size() && equal(x.begin(), x.end(), y.begin()); } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> inline bool operator<(const rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& x, const rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& y) { return lexicographical_compare(x.begin(), x.end(), y.begin(), y.end()); } #ifdef __STL_FUNCTION_TMPL_PARTIAL_ORDER template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> inline void swap(rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& x, rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& y) { x.swap(y); } #endif /* __STL_FUNCTION_TMPL_PARTIAL_ORDER */ template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& rb_tree<Key, Value, KeyOfValue, Compare, Alloc>:: operator=(const rb_tree<Key, Value, KeyOfValue, Compare, Alloc>& x) { if (this != &x) { // Note that Key may be a constant type. clear(); node_count = 0; key_compare = x.key_compare; if (x.root() == 0) { root() = 0; leftmost() = header; rightmost() = header; } else { root() = __copy(x.root(), header); leftmost() = minimum(root()); rightmost() = maximum(root()); node_count = x.node_count; } } return *this; } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::iterator rb_tree<Key, Value, KeyOfValue, Compare, Alloc>:: __insert(base_ptr x_, base_ptr y_, const Value& v) { // 參數x_ 為新值安插點,參數y_ 為安插點之父節點,參數v 為新值。 link_type x = (link_type) x_; link_type y = (link_type) y_; link_type z; // key_compare 是鍵值大小比較準則。應該會是個 function object。 if (y == header || x != 0 || key_compare(KeyOfValue()(v), key(y))) { z = create_node(v); // 產生一個新節點 left(y) = z; // 這使得當 y 即為 header時,leftmost() = z if (y == header) { root() = z; rightmost() = z; } else if (y == leftmost()) // 如果y為最左節點 leftmost() = z; // 維護leftmost(),使它永遠指向最左節點 } else { z = create_node(v); // 產生一個新節點 right(y) = z; // 令新節點成為安插點之父節點 y 的右子節點 if (y == rightmost()) rightmost() = z; // 維護rightmost(),使它永遠指向最右節點 } parent(z) = y; // 設定新節點的父節點 left(z) = 0; // 設定新節點的左子節點 right(z) = 0; // 設定新節點的右子節點 // 新節點的顏色將在 __rb_tree_rebalance() 設定(並調整) __rb_tree_rebalance(z, header->parent); // 參數一為新增節點,參數二為 root ++node_count; // 節點數累加 return iterator(z); // 傳回一個迭代器,指向新增節點 } // 安插新值;節點鍵值允許重複。 // 注意,傳回值是一個 RB-tree 迭代器,指向新增節點 template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::iterator rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::insert_equal(const Value& v) { link_type y = header; link_type x = root(); // 從根節點開始 while (x != 0) { // 從根節點開始,往下尋找適當的安插點 y = x; x = key_compare(KeyOfValue()(v), key(x)) ? left(x) : right(x); // 以上,遇「大」則往左,遇「小於或等於」則往右 } return __insert(x, y, v); } // 安插新值;節點鍵值不允許重複,若重複則安插無效。 // 注意,傳回值是個pair,第一元素是個 RB-tree 迭代器,指向新增節點, // 第二元素表示安插成功與否。 template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> pair<typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::iterator, bool> rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::insert_unique(const Value& v) { link_type y = header; link_type x = root(); // 從根節點開始 bool comp = true; while (x != 0) { // 從根節點開始,往下尋找適當的安插點 y = x; comp = key_compare(KeyOfValue()(v), key(x)); // v 鍵值小於目前節點之鍵值? x = comp ? left(x) : right(x); // 遇「大」則往左,遇「小於或等於」則往右 } // 離開 while 迴圈之後,y 所指即安插點之父節點(此時的它必為葉節點) iterator j = iterator(y); // 令迭代器j指向安插點之父節點 y if (comp) // 如果離開 while 迴圈時 comp 為真(表示遇「大」,將安插於左側) if (j == begin()) // 如果安插點之父節點為最左節點 return pair<iterator,bool>(__insert(x, y, v), true); // 以上,x 為安插點,y 為安插點之父節點,v 為新值。 else // 否則(安插點之父節點不為最左節點) --j; // 調整 j,回頭準備測試... if (key_compare(key(j.node), KeyOfValue()(v))) // 小於新值(表示遇「小」,將安插於右側) return pair<iterator,bool>(__insert(x, y, v), true); // 進行至此,表示新值一定與樹中鍵值重複,那麼就不該插入新值。 return pair<iterator,bool>(j, false); } template <class Key, class Val, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Val, KeyOfValue, Compare, Alloc>::iterator rb_tree<Key, Val, KeyOfValue, Compare, Alloc>::insert_unique(iterator position, const Val& v) { if (position.node == header->left) // begin() if (size() > 0 && key_compare(KeyOfValue()(v), key(position.node))) return __insert(position.node, position.node, v); // first argument just needs to be non-null else return insert_unique(v).first; else if (position.node == header) // end() if (key_compare(key(rightmost()), KeyOfValue()(v))) return __insert(0, rightmost(), v); else return insert_unique(v).first; else { iterator before = position; --before; if (key_compare(key(before.node), KeyOfValue()(v)) && key_compare(KeyOfValue()(v), key(position.node))) if (right(before.node) == 0) return __insert(0, before.node, v); else return __insert(position.node, position.node, v); // first argument just needs to be non-null else return insert_unique(v).first; } } template <class Key, class Val, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Val, KeyOfValue, Compare, Alloc>::iterator rb_tree<Key, Val, KeyOfValue, Compare, Alloc>::insert_equal(iterator position, const Val& v) { if (position.node == header->left) // begin() if (size() > 0 && key_compare(KeyOfValue()(v), key(position.node))) return __insert(position.node, position.node, v); // first argument just needs to be non-null else return insert_equal(v); else if (position.node == header) // end() if (!key_compare(KeyOfValue()(v), key(rightmost()))) return __insert(0, rightmost(), v); else return insert_equal(v); else { iterator before = position; --before; if (!key_compare(KeyOfValue()(v), key(before.node)) && !key_compare(key(position.node), KeyOfValue()(v))) if (right(before.node) == 0) return __insert(0, before.node, v); else return __insert(position.node, position.node, v); // first argument just needs to be non-null else return insert_equal(v); } } #ifdef __STL_MEMBER_TEMPLATES template <class K, class V, class KoV, class Cmp, class Al> template<class II> void rb_tree<K, V, KoV, Cmp, Al>::insert_equal(II first, II last) { for ( ; first != last; ++first) insert_equal(*first); } template <class K, class V, class KoV, class Cmp, class Al> template<class II> void rb_tree<K, V, KoV, Cmp, Al>::insert_unique(II first, II last) { for ( ; first != last; ++first) insert_unique(*first); } #else /* __STL_MEMBER_TEMPLATES */ template <class K, class V, class KoV, class Cmp, class Al> void rb_tree<K, V, KoV, Cmp, Al>::insert_equal(const V* first, const V* last) { for ( ; first != last; ++first) insert_equal(*first); } template <class K, class V, class KoV, class Cmp, class Al> void rb_tree<K, V, KoV, Cmp, Al>::insert_equal(const_iterator first, const_iterator last) { for ( ; first != last; ++first) insert_equal(*first); } template <class K, class V, class KoV, class Cmp, class A> void rb_tree<K, V, KoV, Cmp, A>::insert_unique(const V* first, const V* last) { for ( ; first != last; ++first) insert_unique(*first); } template <class K, class V, class KoV, class Cmp, class A> void rb_tree<K, V, KoV, Cmp, A>::insert_unique(const_iterator first, const_iterator last) { for ( ; first != last; ++first) insert_unique(*first); } #endif /* __STL_MEMBER_TEMPLATES */ template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> inline void rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::erase(iterator position) { link_type y = (link_type) __rb_tree_rebalance_for_erase(position.node, header->parent, header->left, header->right); destroy_node(y); --node_count; } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::size_type rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::erase(const Key& x) { pair<iterator,iterator> p = equal_range(x); size_type n = 0; distance(p.first, p.second, n); erase(p.first, p.second); return n; } template <class K, class V, class KeyOfValue, class Compare, class Alloc> typename rb_tree<K, V, KeyOfValue, Compare, Alloc>::link_type rb_tree<K, V, KeyOfValue, Compare, Alloc>::__copy(link_type x, link_type p) { // structural copy. x and p must be non-null. link_type top = clone_node(x); top->parent = p; __STL_TRY { if (x->right) top->right = __copy(right(x), top); p = top; x = left(x); while (x != 0) { link_type y = clone_node(x); p->left = y; y->parent = p; if (x->right) y->right = __copy(right(x), y); p = y; x = left(x); } } __STL_UNWIND(__erase(top)); return top; } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> void rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::__erase(link_type x) { // erase without rebalancing while (x != 0) { __erase(right(x)); link_type y = left(x); destroy_node(x); x = y; } } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> void rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::erase(iterator first, iterator last) { if (first == begin() && last == end()) clear(); else while (first != last) erase(first++); } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> void rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::erase(const Key* first, const Key* last) { while (first != last) erase(*first++); } // 尋找 RB 樹中是否有鍵值為 k 的節點 template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::iterator rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::find(const Key& k) { link_type y = header; // Last node which is not less than k. link_type x = root(); // Current node. while (x != 0) // 以下,key_compare 是節點鍵值大小比較準則。應該會是個 function object。 if (!key_compare(key(x), k)) // 進行到這裡,表示 x 鍵值大於 k。遇到大值就向左走。 y = x, x = left(x); // 注意語法! else // 進行到這裡,表示 x 鍵值小於 k。遇到小值就向右走。 x = right(x); iterator j = iterator(y); return (j == end() || key_compare(k, key(j.node))) ? end() : j; } // 尋找 RB 樹中是否有鍵值為 k 的節點 template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::const_iterator rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::find(const Key& k) const { link_type y = header; /* Last node which is not less than k. */ link_type x = root(); /* Current node. */ while (x != 0) { // 以下,key_compare 是節點鍵值大小比較準則。應該會是個 function object。 if (!key_compare(key(x), k)) // 進行到這裡,表示 x 鍵值大於 k。遇到大值就向左走。 y = x, x = left(x); // 注意語法! else // 進行到這裡,表示 x 鍵值小於 k。遇到小值就向右走。 x = right(x); } const_iterator j = const_iterator(y); return (j == end() || key_compare(k, key(j.node))) ? end() : j; } // 計算 RB 樹中鍵值為 k 的節點個數 template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::size_type rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::count(const Key& k) const { pair<const_iterator, const_iterator> p = equal_range(k); size_type n = 0; distance(p.first, p.second, n); return n; } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::iterator rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::lower_bound(const Key& k) { link_type y = header; /* Last node which is not less than k. */ link_type x = root(); /* Current node. */ while (x != 0) if (!key_compare(key(x), k)) y = x, x = left(x); else x = right(x); return iterator(y); } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::const_iterator rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::lower_bound(const Key& k) const { link_type y = header; /* Last node which is not less than k. */ link_type x = root(); /* Current node. */ while (x != 0) if (!key_compare(key(x), k)) y = x, x = left(x); else x = right(x); return const_iterator(y); } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::iterator rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::upper_bound(const Key& k) { link_type y = header; /* Last node which is greater than k. */ link_type x = root(); /* Current node. */ while (x != 0) if (key_compare(k, key(x))) y = x, x = left(x); else x = right(x); return iterator(y); } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::const_iterator rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::upper_bound(const Key& k) const { link_type y = header; /* Last node which is greater than k. */ link_type x = root(); /* Current node. */ while (x != 0) if (key_compare(k, key(x))) y = x, x = left(x); else x = right(x); return const_iterator(y); } template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> inline pair<typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::iterator, typename rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::iterator> rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::equal_range(const Key& k) { return pair<iterator, iterator>(lower_bound(k), upper_bound(k)); } template <class Key, class Value, class KoV, class Compare, class Alloc> inline pair<typename rb_tree<Key, Value, KoV, Compare, Alloc>::const_iterator, typename rb_tree<Key, Value, KoV, Compare, Alloc>::const_iterator> rb_tree<Key, Value, KoV, Compare, Alloc>::equal_range(const Key& k) const { return pair<const_iterator,const_iterator>(lower_bound(k), upper_bound(k)); } // 計算從 node 至 root 路徑中的黑節點數量。 inline int __black_count(__rb_tree_node_base* node, __rb_tree_node_base* root) { if (node == 0) return 0; else { int bc = node->color == __rb_tree_black ? 1 : 0; if (node == root) return bc; else return bc + __black_count(node->parent, root); // 累加 } } // 驗證己身這棵樹是否符合 RB 樹的條件 template <class Key, class Value, class KeyOfValue, class Compare, class Alloc> bool rb_tree<Key, Value, KeyOfValue, Compare, Alloc>::__rb_verify() const { // 空樹,符合RB樹標準 if (node_count == 0 || begin() == end()) return node_count == 0 && begin() == end() && header->left == header && header->right == header; // 最左(葉)節點至 root 路徑內的黑節點數 int len = __black_count(leftmost(), root()); // 以下走訪整個RB樹,針對每個節點(從最小到最大)... for (const_iterator it = begin(); it != end(); ++it) { link_type x = (link_type) it.node; // __rb_tree_base_iterator::node link_type L = left(x); // 這是左子節點 link_type R = right(x); // 這是右子節點 if (x->color == __rb_tree_red) if ((L && L->color == __rb_tree_red) || (R && R->color == __rb_tree_red)) return false; // 父子節點同為紅色,不符合 RB 樹的要求。 if (L && key_compare(key(x), key(L))) // 目前節點的鍵值小於左子節點鍵值 return false; // 不符合二元搜尋樹的要求。 if (R && key_compare(key(R), key(x))) // 目前節點的鍵值大於右子節點鍵值 return false; // 不符合二元搜尋樹的要求。 // 「葉節點至 root」路徑內的黑節點數,與「最左節點至 root」路徑內的黑節點數不同。 // 這不符合 RB 樹的要求。 if (!L && !R && __black_count(x, root()) != len) return false; } if (leftmost() != __rb_tree_node_base::minimum(root())) return false; // 最左節點不為最小節點,不符合二元搜尋樹的要求。 if (rightmost() != __rb_tree_node_base::maximum(root())) return false; // 最右節點不為最大節點,不符合二元搜尋樹的要求。 return true; } __STL_END_NAMESPACE #endif /* __SGI_STL_INTERNAL_TREE_H */ // Local Variables: // mode:C++ // End:
posted on 2015-11-23 11:20 zyz913614263 阅读(352) 评论(0) 编辑 收藏 举报