| ///////////////////////////////////////////////////////////////////////////// |
| // |
| // (C) Copyright Ion Gaztanaga 2007. |
| // |
| // Distributed under the Boost Software License, Version 1.0. |
| // (See accompanying file LICENSE_1_0.txt or copy at |
| // http://www.boost.org/LICENSE_1_0.txt) |
| // |
| // See http://www.boost.org/libs/intrusive for documentation. |
| // |
| ///////////////////////////////////////////////////////////////////////////// |
| // The implementation of splay trees is based on the article and code published |
| // in C++ Users Journal "Implementing Splay Trees in C++" (September 1, 2005). |
| // |
| // The code has been modified and (supposely) improved by Ion Gaztanaga. |
| // Here is the header of the file used as base code: |
| // |
| // splay_tree.h -- implementation of a STL complatible splay tree. |
| // |
| // Copyright (c) 2004 Ralf Mattethat |
| // |
| // Permission to copy, use, modify, sell and distribute this software |
| // is granted provided this copyright notice appears in all copies. |
| // This software is provided "as is" without express or implied |
| // warranty, and with no claim as to its suitability for any purpose. |
| // |
| // Please send questions, comments, complaints, performance data, etc to |
| // ralf.mattethat@teknologisk.dk |
| // |
| // Requirements for element type |
| // * must be copy-constructible |
| // * destructor must not throw exception |
| // |
| // Methods marked with note A only throws an exception if the evaluation of the |
| // predicate throws an exception. If an exception is thrown the call has no |
| // effect on the containers state |
| // |
| // Methods marked with note B only throws an exception if the coppy constructor |
| // or assignment operator of the predicate throws an exception. If an exception |
| // is thrown the call has no effect on the containers state |
| // |
| // iterators are only invalidated, if the element pointed to by the iterator |
| // is deleted. The same goes for element references |
| // |
| |
| #ifndef BOOST_INTRUSIVE_SPLAYTREE_ALGORITHMS_HPP |
| #define BOOST_INTRUSIVE_SPLAYTREE_ALGORITHMS_HPP |
| |
| #include <boost/intrusive/detail/config_begin.hpp> |
| #include <boost/intrusive/detail/assert.hpp> |
| #include <boost/intrusive/intrusive_fwd.hpp> |
| #include <cstddef> |
| #include <boost/intrusive/detail/utilities.hpp> |
| #include <boost/intrusive/detail/tree_algorithms.hpp> |
| |
| namespace boost { |
| namespace intrusive { |
| |
| /// @cond |
| namespace detail { |
| |
| template<class NodeTraits> |
| struct splaydown_rollback |
| { |
| typedef typename NodeTraits::node_ptr node_ptr; |
| splaydown_rollback( const node_ptr *pcur_subtree, node_ptr header |
| , node_ptr leftmost , node_ptr rightmost) |
| : pcur_subtree_(pcur_subtree) , header_(header) |
| , leftmost_(leftmost) , rightmost_(rightmost) |
| {} |
| |
| void release() |
| { pcur_subtree_ = 0; } |
| |
| ~splaydown_rollback() |
| { |
| if(pcur_subtree_){ |
| //Exception can only be thrown by comp, but |
| //tree invariants still hold. *pcur_subtree is the current root |
| //so link it to the header. |
| NodeTraits::set_parent(*pcur_subtree_, header_); |
| NodeTraits::set_parent(header_, *pcur_subtree_); |
| //Recover leftmost/rightmost pointers |
| NodeTraits::set_left (header_, leftmost_); |
| NodeTraits::set_right(header_, rightmost_); |
| } |
| } |
| const node_ptr *pcur_subtree_; |
| node_ptr header_, leftmost_, rightmost_; |
| }; |
| |
| } //namespace detail { |
| /// @endcond |
| |
| //! A splay tree is an implementation of a binary search tree. The tree is |
| //! self balancing using the splay algorithm as described in |
| //! |
| //! "Self-Adjusting Binary Search Trees |
| //! by Daniel Dominic Sleator and Robert Endre Tarjan |
| //! AT&T Bell Laboratories, Murray Hill, NJ |
| //! Journal of the ACM, Vol 32, no 3, July 1985, pp 652-686 |
| |
| //! splaytree_algorithms is configured with a NodeTraits class, which encapsulates the |
| //! information about the node to be manipulated. NodeTraits must support the |
| //! following interface: |
| //! |
| //! <b>Typedefs</b>: |
| //! |
| //! <tt>node</tt>: The type of the node that forms the circular list |
| //! |
| //! <tt>node_ptr</tt>: A pointer to a node |
| //! |
| //! <tt>const_node_ptr</tt>: A pointer to a const node |
| //! |
| //! <b>Static functions</b>: |
| //! |
| //! <tt>static node_ptr get_parent(const_node_ptr n);</tt> |
| //! |
| //! <tt>static void set_parent(node_ptr n, node_ptr parent);</tt> |
| //! |
| //! <tt>static node_ptr get_left(const_node_ptr n);</tt> |
| //! |
| //! <tt>static void set_left(node_ptr n, node_ptr left);</tt> |
| //! |
| //! <tt>static node_ptr get_right(const_node_ptr n);</tt> |
| //! |
| //! <tt>static void set_right(node_ptr n, node_ptr right);</tt> |
| template<class NodeTraits> |
| class splaytree_algorithms |
| { |
| /// @cond |
| private: |
| typedef detail::tree_algorithms<NodeTraits> tree_algorithms; |
| /// @endcond |
| |
| public: |
| typedef typename NodeTraits::node node; |
| typedef NodeTraits node_traits; |
| typedef typename NodeTraits::node_ptr node_ptr; |
| typedef typename NodeTraits::const_node_ptr const_node_ptr; |
| |
| //! This type is the information that will be |
| //! filled by insert_unique_check |
| typedef typename tree_algorithms::insert_commit_data insert_commit_data; |
| |
| /// @cond |
| private: |
| static node_ptr uncast(const_node_ptr ptr) |
| { |
| return node_ptr(const_cast<node*>(::boost::intrusive::detail::boost_intrusive_get_pointer(ptr))); |
| } |
| /// @endcond |
| |
| public: |
| static node_ptr begin_node(const_node_ptr header) |
| { return tree_algorithms::begin_node(header); } |
| |
| static node_ptr end_node(const_node_ptr header) |
| { return tree_algorithms::end_node(header); } |
| |
| //! <b>Requires</b>: node is a node of the tree or an node initialized |
| //! by init(...). |
| //! |
| //! <b>Effects</b>: Returns true if the node is initialized by init(). |
| //! |
| //! <b>Complexity</b>: Constant time. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static bool unique(const_node_ptr node) |
| { return tree_algorithms::unique(node); } |
| |
| static void unlink(node_ptr node) |
| { tree_algorithms::unlink(node); } |
| |
| //! <b>Requires</b>: node1 and node2 can't be header nodes |
| //! of two trees. |
| //! |
| //! <b>Effects</b>: Swaps two nodes. After the function node1 will be inserted |
| //! in the position node2 before the function. node2 will be inserted in the |
| //! position node1 had before the function. |
| //! |
| //! <b>Complexity</b>: Logarithmic. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Note</b>: This function will break container ordering invariants if |
| //! node1 and node2 are not equivalent according to the ordering rules. |
| //! |
| //!Experimental function |
| static void swap_nodes(node_ptr node1, node_ptr node2) |
| { |
| if(node1 == node2) |
| return; |
| |
| node_ptr header1(tree_algorithms::get_header(node1)), header2(tree_algorithms::get_header(node2)); |
| swap_nodes(node1, header1, node2, header2); |
| } |
| |
| //! <b>Requires</b>: node1 and node2 can't be header nodes |
| //! of two trees with header header1 and header2. |
| //! |
| //! <b>Effects</b>: Swaps two nodes. After the function node1 will be inserted |
| //! in the position node2 before the function. node2 will be inserted in the |
| //! position node1 had before the function. |
| //! |
| //! <b>Complexity</b>: Constant. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Note</b>: This function will break container ordering invariants if |
| //! node1 and node2 are not equivalent according to the ordering rules. |
| //! |
| //!Experimental function |
| static void swap_nodes(node_ptr node1, node_ptr header1, node_ptr node2, node_ptr header2) |
| { tree_algorithms::swap_nodes(node1, header1, node2, header2); } |
| |
| //! <b>Requires</b>: node_to_be_replaced must be inserted in a tree |
| //! and new_node must not be inserted in a tree. |
| //! |
| //! <b>Effects</b>: Replaces node_to_be_replaced in its position in the |
| //! tree with new_node. The tree does not need to be rebalanced |
| //! |
| //! <b>Complexity</b>: Logarithmic. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Note</b>: This function will break container ordering invariants if |
| //! new_node is not equivalent to node_to_be_replaced according to the |
| //! ordering rules. This function is faster than erasing and inserting |
| //! the node, since no rebalancing and comparison is needed. |
| //! |
| //!Experimental function |
| static void replace_node(node_ptr node_to_be_replaced, node_ptr new_node) |
| { |
| if(node_to_be_replaced == new_node) |
| return; |
| replace_node(node_to_be_replaced, tree_algorithms::get_header(node_to_be_replaced), new_node); |
| } |
| |
| //! <b>Requires</b>: node_to_be_replaced must be inserted in a tree |
| //! with header "header" and new_node must not be inserted in a tree. |
| //! |
| //! <b>Effects</b>: Replaces node_to_be_replaced in its position in the |
| //! tree with new_node. The tree does not need to be rebalanced |
| //! |
| //! <b>Complexity</b>: Constant. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Note</b>: This function will break container ordering invariants if |
| //! new_node is not equivalent to node_to_be_replaced according to the |
| //! ordering rules. This function is faster than erasing and inserting |
| //! the node, since no rebalancing or comparison is needed. |
| //! |
| //!Experimental function |
| static void replace_node(node_ptr node_to_be_replaced, node_ptr header, node_ptr new_node) |
| { tree_algorithms::replace_node(node_to_be_replaced, header, new_node); } |
| |
| //! <b>Requires</b>: p is a node from the tree except the header. |
| //! |
| //! <b>Effects</b>: Returns the next node of the tree. |
| //! |
| //! <b>Complexity</b>: Average constant time. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static node_ptr next_node(node_ptr p) |
| { return tree_algorithms::next_node(p); } |
| |
| //! <b>Requires</b>: p is a node from the tree except the leftmost node. |
| //! |
| //! <b>Effects</b>: Returns the previous node of the tree. |
| //! |
| //! <b>Complexity</b>: Average constant time. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static node_ptr prev_node(node_ptr p) |
| { return tree_algorithms::prev_node(p); } |
| |
| //! <b>Requires</b>: node must not be part of any tree. |
| //! |
| //! <b>Effects</b>: After the function unique(node) == true. |
| //! |
| //! <b>Complexity</b>: Constant. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Nodes</b>: If node is inserted in a tree, this function corrupts the tree. |
| static void init(node_ptr node) |
| { tree_algorithms::init(node); } |
| |
| //! <b>Requires</b>: node must not be part of any tree. |
| //! |
| //! <b>Effects</b>: Initializes the header to represent an empty tree. |
| //! unique(header) == true. |
| //! |
| //! <b>Complexity</b>: Constant. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Nodes</b>: If node is inserted in a tree, this function corrupts the tree. |
| static void init_header(node_ptr header) |
| { tree_algorithms::init_header(header); } |
| |
| //! <b>Requires</b>: "disposer" must be an object function |
| //! taking a node_ptr parameter and shouldn't throw. |
| //! |
| //! <b>Effects</b>: Empties the target tree calling |
| //! <tt>void disposer::operator()(node_ptr)</tt> for every node of the tree |
| //! except the header. |
| //! |
| //! <b>Complexity</b>: Linear to the number of element of the source tree plus the. |
| //! number of elements of tree target tree when calling this function. |
| //! |
| //! <b>Throws</b>: If cloner functor throws. If this happens target nodes are disposed. |
| template<class Disposer> |
| static void clear_and_dispose(node_ptr header, Disposer disposer) |
| { tree_algorithms::clear_and_dispose(header, disposer); } |
| |
| //! <b>Requires</b>: node is a node of the tree but it's not the header. |
| //! |
| //! <b>Effects</b>: Returns the number of nodes of the subtree. |
| //! |
| //! <b>Complexity</b>: Linear time. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static std::size_t count(const_node_ptr node) |
| { return tree_algorithms::count(node); } |
| |
| //! <b>Requires</b>: header is the header node of the tree. |
| //! |
| //! <b>Effects</b>: Returns the number of nodes above the header. |
| //! |
| //! <b>Complexity</b>: Linear time. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static std::size_t size(const_node_ptr header) |
| { return tree_algorithms::size(header); } |
| |
| //! <b>Requires</b>: header1 and header2 must be the header nodes |
| //! of two trees. |
| //! |
| //! <b>Effects</b>: Swaps two trees. After the function header1 will contain |
| //! links to the second tree and header2 will have links to the first tree. |
| //! |
| //! <b>Complexity</b>: Constant. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static void swap_tree(node_ptr header1, node_ptr header2) |
| { return tree_algorithms::swap_tree(header1, header2); } |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! "commit_data" must have been obtained from a previous call to |
| //! "insert_unique_check". No objects should have been inserted or erased |
| //! from the set between the "insert_unique_check" that filled "commit_data" |
| //! and the call to "insert_commit". |
| //! |
| //! |
| //! <b>Effects</b>: Inserts new_node in the set using the information obtained |
| //! from the "commit_data" that a previous "insert_check" filled. |
| //! |
| //! <b>Complexity</b>: Constant time. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Notes</b>: This function has only sense if a "insert_unique_check" has been |
| //! previously executed to fill "commit_data". No value should be inserted or |
| //! erased between the "insert_check" and "insert_commit" calls. |
| static void insert_unique_commit |
| (node_ptr header, node_ptr new_value, const insert_commit_data &commit_data) |
| { tree_algorithms::insert_unique_commit(header, new_value, commit_data); } |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! KeyNodePtrCompare is a function object that induces a strict weak |
| //! ordering compatible with the strict weak ordering used to create the |
| //! the tree. NodePtrCompare compares KeyType with a node_ptr. |
| //! |
| //! <b>Effects</b>: Checks if there is an equivalent node to "key" in the |
| //! tree according to "comp" and obtains the needed information to realize |
| //! a constant-time node insertion if there is no equivalent node. |
| //! |
| //! <b>Returns</b>: If there is an equivalent value |
| //! returns a pair containing a node_ptr to the already present node |
| //! and false. If there is not equivalent key can be inserted returns true |
| //! in the returned pair's boolean and fills "commit_data" that is meant to |
| //! be used with the "insert_commit" function to achieve a constant-time |
| //! insertion function. |
| //! |
| //! <b>Complexity</b>: Average complexity is at most logarithmic. |
| //! |
| //! <b>Throws</b>: If "comp" throws. |
| //! |
| //! <b>Notes</b>: This function is used to improve performance when constructing |
| //! a node is expensive and the user does not want to have two equivalent nodes |
| //! in the tree: if there is an equivalent value |
| //! the constructed object must be discarded. Many times, the part of the |
| //! node that is used to impose the order is much cheaper to construct |
| //! than the node and this function offers the possibility to use that part |
| //! to check if the insertion will be successful. |
| //! |
| //! If the check is successful, the user can construct the node and use |
| //! "insert_commit" to insert the node in constant-time. This gives a total |
| //! logarithmic complexity to the insertion: check(O(log(N)) + commit(O(1)). |
| //! |
| //! "commit_data" remains valid for a subsequent "insert_unique_commit" only |
| //! if no more objects are inserted or erased from the set. |
| template<class KeyType, class KeyNodePtrCompare> |
| static std::pair<node_ptr, bool> insert_unique_check |
| (node_ptr header, const KeyType &key |
| ,KeyNodePtrCompare comp, insert_commit_data &commit_data) |
| { |
| splay_down(header, key, comp); |
| return tree_algorithms::insert_unique_check(header, key, comp, commit_data); |
| } |
| |
| template<class KeyType, class KeyNodePtrCompare> |
| static std::pair<node_ptr, bool> insert_unique_check |
| (node_ptr header, node_ptr hint, const KeyType &key |
| ,KeyNodePtrCompare comp, insert_commit_data &commit_data) |
| { |
| splay_down(header, key, comp); |
| return tree_algorithms::insert_unique_check(header, hint, key, comp, commit_data); |
| } |
| |
| static bool is_header(const_node_ptr p) |
| { return tree_algorithms::is_header(p); } |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! KeyNodePtrCompare is a function object that induces a strict weak |
| //! ordering compatible with the strict weak ordering used to create the |
| //! the tree. KeyNodePtrCompare can compare KeyType with tree's node_ptrs. |
| //! |
| //! <b>Effects</b>: Returns an node_ptr to the element that is equivalent to |
| //! "key" according to "comp" or "header" if that element does not exist. |
| //! |
| //! <b>Complexity</b>: Logarithmic. |
| //! |
| //! <b>Throws</b>: If "comp" throws. |
| template<class KeyType, class KeyNodePtrCompare> |
| static node_ptr find |
| (const_node_ptr header, const KeyType &key, KeyNodePtrCompare comp, bool splay = true) |
| { |
| if(splay) |
| splay_down(uncast(header), key, comp); |
| node_ptr end = uncast(header); |
| node_ptr y = lower_bound(header, key, comp, false); |
| node_ptr r = (y == end || comp(key, y)) ? end : y; |
| return r; |
| } |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! KeyNodePtrCompare is a function object that induces a strict weak |
| //! ordering compatible with the strict weak ordering used to create the |
| //! the tree. KeyNodePtrCompare can compare KeyType with tree's node_ptrs. |
| //! |
| //! <b>Effects</b>: Returns an a pair of node_ptr delimiting a range containing |
| //! all elements that are equivalent to "key" according to "comp" or an |
| //! empty range that indicates the position where those elements would be |
| //! if they there are no equivalent elements. |
| //! |
| //! <b>Complexity</b>: Logarithmic. |
| //! |
| //! <b>Throws</b>: If "comp" throws. |
| template<class KeyType, class KeyNodePtrCompare> |
| static std::pair<node_ptr, node_ptr> equal_range |
| (const_node_ptr header, const KeyType &key, KeyNodePtrCompare comp, bool splay = true) |
| { |
| //if(splay) |
| //splay_down(uncast(header), key, comp); |
| std::pair<node_ptr, node_ptr> ret = |
| tree_algorithms::equal_range(header, key, comp); |
| |
| if(splay) |
| splay_up(ret.first, uncast(header)); |
| return ret; |
| } |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! KeyNodePtrCompare is a function object that induces a strict weak |
| //! ordering compatible with the strict weak ordering used to create the |
| //! the tree. KeyNodePtrCompare can compare KeyType with tree's node_ptrs. |
| //! |
| //! <b>Effects</b>: Returns an node_ptr to the first element that is |
| //! not less than "key" according to "comp" or "header" if that element does |
| //! not exist. |
| //! |
| //! <b>Complexity</b>: Logarithmic. |
| //! |
| //! <b>Throws</b>: If "comp" throws. |
| template<class KeyType, class KeyNodePtrCompare> |
| static node_ptr lower_bound |
| (const_node_ptr header, const KeyType &key, KeyNodePtrCompare comp, bool splay = true) |
| { |
| //if(splay) |
| //splay_down(uncast(header), key, comp); |
| node_ptr y = tree_algorithms::lower_bound(header, key, comp); |
| if(splay) |
| splay_up(y, uncast(header)); |
| return y; |
| } |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! KeyNodePtrCompare is a function object that induces a strict weak |
| //! ordering compatible with the strict weak ordering used to create the |
| //! the tree. KeyNodePtrCompare can compare KeyType with tree's node_ptrs. |
| //! |
| //! <b>Effects</b>: Returns an node_ptr to the first element that is greater |
| //! than "key" according to "comp" or "header" if that element does not exist. |
| //! |
| //! <b>Complexity</b>: Logarithmic. |
| //! |
| //! <b>Throws</b>: If "comp" throws. |
| template<class KeyType, class KeyNodePtrCompare> |
| static node_ptr upper_bound |
| (const_node_ptr header, const KeyType &key, KeyNodePtrCompare comp, bool splay = true) |
| { |
| //if(splay) |
| //splay_down(uncast(header), key, comp); |
| node_ptr y = tree_algorithms::upper_bound(header, key, comp); |
| if(splay) |
| splay_up(y, uncast(header)); |
| return y; |
| } |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! NodePtrCompare is a function object that induces a strict weak |
| //! ordering compatible with the strict weak ordering used to create the |
| //! the tree. NodePtrCompare compares two node_ptrs. "hint" is node from |
| //! the "header"'s tree. |
| //! |
| //! <b>Effects</b>: Inserts new_node into the tree, using "hint" as a hint to |
| //! where it will be inserted. If "hint" is the upper_bound |
| //! the insertion takes constant time (two comparisons in the worst case). |
| //! |
| //! <b>Complexity</b>: Logarithmic in general, but it is amortized |
| //! constant time if new_node is inserted immediately before "hint". |
| //! |
| //! <b>Throws</b>: If "comp" throws. |
| template<class NodePtrCompare> |
| static node_ptr insert_equal |
| (node_ptr header, node_ptr hint, node_ptr new_node, NodePtrCompare comp) |
| { |
| splay_down(header, new_node, comp); |
| return tree_algorithms::insert_equal(header, hint, new_node, comp); |
| } |
| |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! "pos" must be a valid iterator or header (end) node. |
| //! "pos" must be an iterator pointing to the successor to "new_node" |
| //! once inserted according to the order of already inserted nodes. This function does not |
| //! check "pos" and this precondition must be guaranteed by the caller. |
| //! |
| //! <b>Effects</b>: Inserts new_node into the tree before "pos". |
| //! |
| //! <b>Complexity</b>: Constant-time. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Note</b>: If "pos" is not the successor of the newly inserted "new_node" |
| //! tree invariants might be broken. |
| static node_ptr insert_before |
| (node_ptr header, node_ptr pos, node_ptr new_node) |
| { |
| tree_algorithms::insert_before(header, pos, new_node); |
| splay_up(new_node, header); |
| return new_node; |
| } |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! "new_node" must be, according to the used ordering no less than the |
| //! greatest inserted key. |
| //! |
| //! <b>Effects</b>: Inserts new_node into the tree before "pos". |
| //! |
| //! <b>Complexity</b>: Constant-time. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Note</b>: If "new_node" is less than the greatest inserted key |
| //! tree invariants are broken. This function is slightly faster than |
| //! using "insert_before". |
| static void push_back(node_ptr header, node_ptr new_node) |
| { |
| tree_algorithms::push_back(header, new_node); |
| splay_up(new_node, header); |
| } |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! "new_node" must be, according to the used ordering, no greater than the |
| //! lowest inserted key. |
| //! |
| //! <b>Effects</b>: Inserts new_node into the tree before "pos". |
| //! |
| //! <b>Complexity</b>: Constant-time. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Note</b>: If "new_node" is greater than the lowest inserted key |
| //! tree invariants are broken. This function is slightly faster than |
| //! using "insert_before". |
| static void push_front(node_ptr header, node_ptr new_node) |
| { |
| tree_algorithms::push_front(header, new_node); |
| splay_up(new_node, header); |
| } |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! NodePtrCompare is a function object that induces a strict weak |
| //! ordering compatible with the strict weak ordering used to create the |
| //! the tree. NodePtrCompare compares two node_ptrs. |
| //! |
| //! <b>Effects</b>: Inserts new_node into the tree before the upper bound |
| //! according to "comp". |
| //! |
| //! <b>Complexity</b>: Average complexity for insert element is at |
| //! most logarithmic. |
| //! |
| //! <b>Throws</b>: If "comp" throws. |
| template<class NodePtrCompare> |
| static node_ptr insert_equal_upper_bound |
| (node_ptr header, node_ptr new_node, NodePtrCompare comp) |
| { |
| splay_down(header, new_node, comp); |
| return tree_algorithms::insert_equal_upper_bound(header, new_node, comp); |
| } |
| |
| //! <b>Requires</b>: "header" must be the header node of a tree. |
| //! NodePtrCompare is a function object that induces a strict weak |
| //! ordering compatible with the strict weak ordering used to create the |
| //! the tree. NodePtrCompare compares two node_ptrs. |
| //! |
| //! <b>Effects</b>: Inserts new_node into the tree before the lower bound |
| //! according to "comp". |
| //! |
| //! <b>Complexity</b>: Average complexity for insert element is at |
| //! most logarithmic. |
| //! |
| //! <b>Throws</b>: If "comp" throws. |
| template<class NodePtrCompare> |
| static node_ptr insert_equal_lower_bound |
| (node_ptr header, node_ptr new_node, NodePtrCompare comp) |
| { |
| splay_down(header, new_node, comp); |
| return tree_algorithms::insert_equal_lower_bound(header, new_node, comp); |
| } |
| |
| //! <b>Requires</b>: "cloner" must be a function |
| //! object taking a node_ptr and returning a new cloned node of it. "disposer" must |
| //! take a node_ptr and shouldn't throw. |
| //! |
| //! <b>Effects</b>: First empties target tree calling |
| //! <tt>void disposer::operator()(node_ptr)</tt> for every node of the tree |
| //! except the header. |
| //! |
| //! Then, duplicates the entire tree pointed by "source_header" cloning each |
| //! source node with <tt>node_ptr Cloner::operator()(node_ptr)</tt> to obtain |
| //! the nodes of the target tree. If "cloner" throws, the cloned target nodes |
| //! are disposed using <tt>void disposer(node_ptr)</tt>. |
| //! |
| //! <b>Complexity</b>: Linear to the number of element of the source tree plus the. |
| //! number of elements of tree target tree when calling this function. |
| //! |
| //! <b>Throws</b>: If cloner functor throws. If this happens target nodes are disposed. |
| template <class Cloner, class Disposer> |
| static void clone |
| (const_node_ptr source_header, node_ptr target_header, Cloner cloner, Disposer disposer) |
| { tree_algorithms::clone(source_header, target_header, cloner, disposer); } |
| |
| // delete node | complexity : constant | exception : nothrow |
| static void erase(node_ptr header, node_ptr z, bool splay = true) |
| { |
| // node_base* n = t->right; |
| // if( t->left != 0 ){ |
| // node_base* l = t->previous(); |
| // splay_up( l , t ); |
| // n = t->left; |
| // n->right = t->right; |
| // if( n->right != 0 ) |
| // n->right->parent = n; |
| // } |
| // |
| // if( n != 0 ) |
| // n->parent = t->parent; |
| // |
| // if( t->parent->left == t ) |
| // t->parent->left = n; |
| // else // must be ( t->parent->right == t ) |
| // t->parent->right = n; |
| // |
| // if( data_->parent == t ) |
| // data_->parent = find_leftmost(); |
| //posibility 1 |
| if(splay && NodeTraits::get_left(z)){ |
| splay_up(prev_node(z), header); |
| } |
| /* |
| //possibility 2 |
| if(splay && NodeTraits::get_left(z) != 0 ){ |
| node_ptr l = NodeTraits::get_left(z); |
| splay_up(l, header); |
| }*//* |
| if(splay && NodeTraits::get_left(z) != 0 ){ |
| node_ptr l = prev_node(z); |
| splay_up_impl(l, z); |
| }*/ |
| /* |
| //possibility 4 |
| if(splay){ |
| splay_up(z, header); |
| }*/ |
| |
| //if(splay) |
| //splay_up(z, header); |
| tree_algorithms::erase(header, z); |
| } |
| |
| // bottom-up splay, use data_ as parent for n | complexity : logarithmic | exception : nothrow |
| static void splay_up(node_ptr n, node_ptr header) |
| { |
| if(n == header){ // do a splay for the right most node instead |
| // this is to boost performance of equal_range/count on equivalent containers in the case |
| // where there are many equal elements at the end |
| n = NodeTraits::get_right(header); |
| } |
| |
| node_ptr t = header; |
| |
| if( n == t ) return; |
| |
| for( ;; ){ |
| node_ptr p(NodeTraits::get_parent(n)); |
| node_ptr g(NodeTraits::get_parent(p)); |
| |
| if( p == t ) break; |
| |
| if( g == t ){ |
| // zig |
| rotate(n); |
| } |
| else if ((NodeTraits::get_left(p) == n && NodeTraits::get_left(g) == p) || |
| (NodeTraits::get_right(p) == n && NodeTraits::get_right(g) == p) ){ |
| // zig-zig |
| rotate(p); |
| rotate(n); |
| } |
| else{ |
| // zig-zag |
| rotate(n); |
| rotate(n); |
| } |
| } |
| } |
| |
| // top-down splay | complexity : logarithmic | exception : strong, note A |
| template<class KeyType, class KeyNodePtrCompare> |
| static node_ptr splay_down(node_ptr header, const KeyType &key, KeyNodePtrCompare comp) |
| { |
| if(!NodeTraits::get_parent(header)) |
| return header; |
| //Most splay tree implementations use a dummy/null node to implement. |
| //this function. This has some problems for a generic library like Intrusive: |
| // |
| // * The node might not have a default constructor. |
| // * The default constructor could throw. |
| // |
| //We already have a header node. Leftmost and rightmost nodes of the tree |
| //are not changed when splaying (because the invariants of the tree don't |
| //change) We can back up them, use the header as the null node and |
| //reassign old values after the function has been completed. |
| node_ptr t = NodeTraits::get_parent(header); |
| //Check if tree has a single node |
| if(!NodeTraits::get_left(t) && !NodeTraits::get_right(t)) |
| return t; |
| //Backup leftmost/rightmost |
| node_ptr leftmost (NodeTraits::get_left(header)); |
| node_ptr rightmost(NodeTraits::get_right(header)); |
| { |
| detail::splaydown_rollback<NodeTraits> rollback(&t, header, leftmost, rightmost); |
| node_ptr null = header; |
| node_ptr l = null; |
| node_ptr r = null; |
| |
| for( ;; ){ |
| if(comp(key, t)){ |
| if(NodeTraits::get_left(t) == 0 ) |
| break; |
| if(comp(key, NodeTraits::get_left(t))){ |
| t = tree_algorithms::rotate_right(t); |
| |
| if(NodeTraits::get_left(t) == 0) |
| break; |
| link_right(t, r); |
| } |
| else if(comp(NodeTraits::get_left(t), key)){ |
| link_right(t, r); |
| |
| if(NodeTraits::get_right(t) == 0 ) |
| break; |
| link_left(t, l); |
| } |
| else{ |
| link_right(t, r); |
| } |
| } |
| else if(comp(t, key)){ |
| if(NodeTraits::get_right(t) == 0 ) |
| break; |
| |
| if(comp(NodeTraits::get_right(t), key)){ |
| t = tree_algorithms::rotate_left( t ); |
| |
| if(NodeTraits::get_right(t) == 0 ) |
| break; |
| link_left(t, l); |
| } |
| else if(comp(key, NodeTraits::get_right(t))){ |
| link_left(t, l); |
| |
| if(NodeTraits::get_left(t) == 0) |
| break; |
| |
| link_right(t, r); |
| } |
| else{ |
| link_left(t, l); |
| } |
| } |
| else{ |
| break; |
| } |
| } |
| |
| assemble(t, l, r, null); |
| rollback.release(); |
| } |
| |
| //t is the current root |
| NodeTraits::set_parent(header, t); |
| NodeTraits::set_parent(t, header); |
| //Recover leftmost/rightmost pointers |
| NodeTraits::set_left (header, leftmost); |
| NodeTraits::set_right(header, rightmost); |
| return t; |
| } |
| |
| //! <b>Requires</b>: header must be the header of a tree. |
| //! |
| //! <b>Effects</b>: Rebalances the tree. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Complexity</b>: Linear. |
| static void rebalance(node_ptr header) |
| { tree_algorithms::rebalance(header); } |
| |
| //! <b>Requires</b>: old_root is a node of a tree. |
| //! |
| //! <b>Effects</b>: Rebalances the subtree rooted at old_root. |
| //! |
| //! <b>Returns</b>: The new root of the subtree. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Complexity</b>: Linear. |
| static node_ptr rebalance_subtree(node_ptr old_root) |
| { return tree_algorithms::rebalance_subtree(old_root); } |
| |
| |
| //! <b>Requires</b>: "n" must be a node inserted in a tree. |
| //! |
| //! <b>Effects</b>: Returns a pointer to the header node of the tree. |
| //! |
| //! <b>Complexity</b>: Logarithmic. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static node_ptr get_header(node_ptr n) |
| { return tree_algorithms::get_header(n); } |
| |
| private: |
| |
| /// @cond |
| |
| // assemble the three sub-trees into new tree pointed to by t | complexity : constant | exception : nothrow |
| static void assemble( node_ptr t, node_ptr l, node_ptr r, const_node_ptr null_node ) |
| { |
| NodeTraits::set_right(l, NodeTraits::get_left(t)); |
| NodeTraits::set_left(r, NodeTraits::get_right(t)); |
| |
| if(NodeTraits::get_right(l) != 0){ |
| NodeTraits::set_parent(NodeTraits::get_right(l), l); |
| } |
| |
| if(NodeTraits::get_left(r) != 0){ |
| NodeTraits::set_parent(NodeTraits::get_left(r), r); |
| } |
| |
| NodeTraits::set_left (t, NodeTraits::get_right(null_node)); |
| NodeTraits::set_right(t, NodeTraits::get_left(null_node)); |
| |
| if( NodeTraits::get_left(t) != 0 ){ |
| NodeTraits::set_parent(NodeTraits::get_left(t), t); |
| } |
| |
| if( NodeTraits::get_right(t) ){ |
| NodeTraits::set_parent(NodeTraits::get_right(t), t); |
| } |
| } |
| |
| // break link to left child node and attach it to left tree pointed to by l | complexity : constant | exception : nothrow |
| static void link_left(node_ptr& t, node_ptr& l) |
| { |
| NodeTraits::set_right(l, t); |
| NodeTraits::set_parent(t, l); |
| l = t; |
| t = NodeTraits::get_right(t); |
| } |
| |
| // break link to right child node and attach it to right tree pointed to by r | complexity : constant | exception : nothrow |
| static void link_right(node_ptr& t, node_ptr& r) |
| { |
| NodeTraits::set_left(r, t); |
| NodeTraits::set_parent(t, r); |
| r = t; |
| t = NodeTraits::get_left(t); |
| } |
| |
| // rotate n with its parent | complexity : constant | exception : nothrow |
| static void rotate(node_ptr n) |
| { |
| node_ptr p = NodeTraits::get_parent(n); |
| node_ptr g = NodeTraits::get_parent(p); |
| //Test if g is header before breaking tree |
| //invariants that would make is_header invalid |
| bool g_is_header = is_header(g); |
| |
| if(NodeTraits::get_left(p) == n){ |
| NodeTraits::set_left(p, NodeTraits::get_right(n)); |
| if(NodeTraits::get_left(p) != 0) |
| NodeTraits::set_parent(NodeTraits::get_left(p), p); |
| NodeTraits::set_right(n, p); |
| } |
| else{ // must be ( p->right == n ) |
| NodeTraits::set_right(p, NodeTraits::get_left(n)); |
| if(NodeTraits::get_right(p) != 0) |
| NodeTraits::set_parent(NodeTraits::get_right(p), p); |
| NodeTraits::set_left(n, p); |
| } |
| |
| NodeTraits::set_parent(p, n); |
| NodeTraits::set_parent(n, g); |
| |
| if(g_is_header){ |
| if(NodeTraits::get_parent(g) == p) |
| NodeTraits::set_parent(g, n); |
| else{//must be ( g->right == p ) |
| BOOST_INTRUSIVE_INVARIANT_ASSERT(0); |
| NodeTraits::set_right(g, n); |
| } |
| } |
| else{ |
| if(NodeTraits::get_left(g) == p) |
| NodeTraits::set_left(g, n); |
| else //must be ( g->right == p ) |
| NodeTraits::set_right(g, n); |
| } |
| } |
| |
| /// @endcond |
| }; |
| |
| } //namespace intrusive |
| } //namespace boost |
| |
| #include <boost/intrusive/detail/config_end.hpp> |
| |
| #endif //BOOST_INTRUSIVE_SPLAYTREE_ALGORITHMS_HPP |