| ///////////////////////////////////////////////////////////////////////////// |
| // |
| // (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. |
| // |
| ///////////////////////////////////////////////////////////////////////////// |
| |
| #ifndef BOOST_INTRUSIVE_TREE_ALGORITHMS_HPP |
| #define BOOST_INTRUSIVE_TREE_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> |
| //iG pending #include <boost/pointer_cast.hpp> |
| |
| namespace boost { |
| namespace intrusive { |
| namespace detail { |
| |
| //! This is an implementation of a binary search tree. |
| //! A node in the search tree has references to its children and its parent. This |
| //! is to allow traversal of the whole tree from a given node making the |
| //! implementation of iterator a pointer to a node. |
| //! At the top of the tree a node is used specially. This node's parent pointer |
| //! is pointing to the root of the tree. Its left pointer points to the |
| //! leftmost node in the tree and the right pointer to the rightmost one. |
| //! This node is used to represent the end-iterator. |
| //! |
| //! +---------+ |
| //! header------------------------------>| | |
| //! | | |
| //! +----------(left)--------| |--------(right)---------+ |
| //! | +---------+ | |
| //! | | | |
| //! | | (parent) | |
| //! | | | |
| //! | | | |
| //! | +---------+ | |
| //! root of tree ..|......................> | | | |
| //! | | D | | |
| //! | | | | |
| //! | +-------+---------+-------+ | |
| //! | | | | |
| //! | | | | |
| //! | | | | |
| //! | | | | |
| //! | | | | |
| //! | +---------+ +---------+ | |
| //! | | | | | | |
| //! | | B | | F | | |
| //! | | | | | | |
| //! | +--+---------+--+ +--+---------+--+ | |
| //! | | | | | | |
| //! | | | | | | |
| //! | | | | | | |
| //! | +---+-----+ +-----+---+ +---+-----+ +-----+---+ | |
| //! +-->| | | | | | | |<--+ |
| //! | A | | C | | E | | G | |
| //! | | | | | | | | |
| //! +---------+ +---------+ +---------+ +---------+ |
| //! |
| |
| //! tree_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 tree_algorithms |
| { |
| 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 |
| struct insert_commit_data |
| { |
| insert_commit_data() |
| : link_left(false) |
| , node(0) |
| {} |
| bool link_left; |
| node_ptr node; |
| }; |
| |
| struct nop_erase_fixup |
| { |
| void operator()(node_ptr, node_ptr){} |
| }; |
| |
| /// @cond |
| private: |
| template<class Disposer> |
| struct dispose_subtree_disposer |
| { |
| dispose_subtree_disposer(Disposer &disp, node_ptr subtree) |
| : disposer_(&disp), subtree_(subtree) |
| {} |
| |
| void release() |
| { disposer_ = 0; } |
| |
| ~dispose_subtree_disposer() |
| { |
| if(disposer_){ |
| dispose_subtree(subtree_, *disposer_); |
| } |
| } |
| Disposer *disposer_; |
| node_ptr subtree_; |
| }; |
| |
| static node_ptr uncast(const_node_ptr ptr) |
| { |
| return node_ptr(const_cast<node*>(::boost::intrusive::detail::boost_intrusive_get_pointer(ptr))); |
| //iG pending return node_ptr(boost::const_pointer_cast<node>(ptr)); |
| } |
| /// @endcond |
| |
| public: |
| static node_ptr begin_node(const_node_ptr header) |
| { return node_traits::get_left(header); } |
| |
| static node_ptr end_node(const_node_ptr header) |
| { return uncast(header); } |
| |
| //! <b>Requires</b>: node is a node of the tree or an node initialized |
| //! by init(...) or init_node. |
| //! |
| //! <b>Effects</b>: Returns true if the node is initialized by init() or init_node(). |
| //! |
| //! <b>Complexity</b>: Constant time. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static bool unique(const_node_ptr node) |
| { return !NodeTraits::get_parent(node); } |
| |
| static node_ptr get_header(const_node_ptr node) |
| { |
| node_ptr h = uncast(node); |
| if(NodeTraits::get_parent(node)){ |
| h = NodeTraits::get_parent(node); |
| while(!is_header(h)) |
| h = NodeTraits::get_parent(h); |
| } |
| return h; |
| } |
| |
| //! <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(get_header(node1)), header2(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) |
| { |
| if(node1 == node2) |
| return; |
| |
| //node1 and node2 must not be header nodes |
| //BOOST_INTRUSIVE_INVARIANT_ASSERT((header1 != node1 && header2 != node2)); |
| if(header1 != header2){ |
| //Update header1 if necessary |
| if(node1 == NodeTraits::get_left(header1)){ |
| NodeTraits::set_left(header1, node2); |
| } |
| |
| if(node1 == NodeTraits::get_right(header1)){ |
| NodeTraits::set_right(header1, node2); |
| } |
| |
| if(node1 == NodeTraits::get_parent(header1)){ |
| NodeTraits::set_parent(header1, node2); |
| } |
| |
| //Update header2 if necessary |
| if(node2 == NodeTraits::get_left(header2)){ |
| NodeTraits::set_left(header2, node1); |
| } |
| |
| if(node2 == NodeTraits::get_right(header2)){ |
| NodeTraits::set_right(header2, node1); |
| } |
| |
| if(node2 == NodeTraits::get_parent(header2)){ |
| NodeTraits::set_parent(header2, node1); |
| } |
| } |
| else{ |
| //If both nodes are from the same tree |
| //Update header if necessary |
| if(node1 == NodeTraits::get_left(header1)){ |
| NodeTraits::set_left(header1, node2); |
| } |
| else if(node2 == NodeTraits::get_left(header2)){ |
| NodeTraits::set_left(header2, node1); |
| } |
| |
| if(node1 == NodeTraits::get_right(header1)){ |
| NodeTraits::set_right(header1, node2); |
| } |
| else if(node2 == NodeTraits::get_right(header2)){ |
| NodeTraits::set_right(header2, node1); |
| } |
| |
| if(node1 == NodeTraits::get_parent(header1)){ |
| NodeTraits::set_parent(header1, node2); |
| } |
| else if(node2 == NodeTraits::get_parent(header2)){ |
| NodeTraits::set_parent(header2, node1); |
| } |
| |
| //Adjust data in nodes to be swapped |
| //so that final link swap works as expected |
| if(node1 == NodeTraits::get_parent(node2)){ |
| NodeTraits::set_parent(node2, node2); |
| |
| if(node2 == NodeTraits::get_right(node1)){ |
| NodeTraits::set_right(node1, node1); |
| } |
| else{ |
| NodeTraits::set_left(node1, node1); |
| } |
| } |
| else if(node2 == NodeTraits::get_parent(node1)){ |
| NodeTraits::set_parent(node1, node1); |
| |
| if(node1 == NodeTraits::get_right(node2)){ |
| NodeTraits::set_right(node2, node2); |
| } |
| else{ |
| NodeTraits::set_left(node2, node2); |
| } |
| } |
| } |
| |
| //Now swap all the links |
| node_ptr temp; |
| //swap left link |
| temp = NodeTraits::get_left(node1); |
| NodeTraits::set_left(node1, NodeTraits::get_left(node2)); |
| NodeTraits::set_left(node2, temp); |
| //swap right link |
| temp = NodeTraits::get_right(node1); |
| NodeTraits::set_right(node1, NodeTraits::get_right(node2)); |
| NodeTraits::set_right(node2, temp); |
| //swap parent link |
| temp = NodeTraits::get_parent(node1); |
| NodeTraits::set_parent(node1, NodeTraits::get_parent(node2)); |
| NodeTraits::set_parent(node2, temp); |
| |
| //Now adjust adjacent nodes for newly inserted node 1 |
| if((temp = NodeTraits::get_left(node1))){ |
| NodeTraits::set_parent(temp, node1); |
| } |
| if((temp = NodeTraits::get_right(node1))){ |
| NodeTraits::set_parent(temp, node1); |
| } |
| if((temp = NodeTraits::get_parent(node1)) && |
| //The header has been already updated so avoid it |
| temp != header2){ |
| if(NodeTraits::get_left(temp) == node2){ |
| NodeTraits::set_left(temp, node1); |
| } |
| if(NodeTraits::get_right(temp) == node2){ |
| NodeTraits::set_right(temp, node1); |
| } |
| } |
| //Now adjust adjacent nodes for newly inserted node 2 |
| if((temp = NodeTraits::get_left(node2))){ |
| NodeTraits::set_parent(temp, node2); |
| } |
| if((temp = NodeTraits::get_right(node2))){ |
| NodeTraits::set_parent(temp, node2); |
| } |
| if((temp = NodeTraits::get_parent(node2)) && |
| //The header has been already updated so avoid it |
| temp != header1){ |
| if(NodeTraits::get_left(temp) == node1){ |
| NodeTraits::set_left(temp, node2); |
| } |
| if(NodeTraits::get_right(temp) == node1){ |
| NodeTraits::set_right(temp, node2); |
| } |
| } |
| } |
| |
| //! <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, 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) |
| { |
| if(node_to_be_replaced == new_node) |
| return; |
| |
| //Update header if necessary |
| if(node_to_be_replaced == NodeTraits::get_left(header)){ |
| NodeTraits::set_left(header, new_node); |
| } |
| |
| if(node_to_be_replaced == NodeTraits::get_right(header)){ |
| NodeTraits::set_right(header, new_node); |
| } |
| |
| if(node_to_be_replaced == NodeTraits::get_parent(header)){ |
| NodeTraits::set_parent(header, new_node); |
| } |
| |
| //Now set data from the original node |
| node_ptr temp; |
| NodeTraits::set_left(new_node, NodeTraits::get_left(node_to_be_replaced)); |
| NodeTraits::set_right(new_node, NodeTraits::get_right(node_to_be_replaced)); |
| NodeTraits::set_parent(new_node, NodeTraits::get_parent(node_to_be_replaced)); |
| |
| //Now adjust adjacent nodes for newly inserted node |
| if((temp = NodeTraits::get_left(new_node))){ |
| NodeTraits::set_parent(temp, new_node); |
| } |
| if((temp = NodeTraits::get_right(new_node))){ |
| NodeTraits::set_parent(temp, new_node); |
| } |
| if((temp = NodeTraits::get_parent(new_node)) && |
| //The header has been already updated so avoid it |
| temp != header){ |
| if(NodeTraits::get_left(temp) == node_to_be_replaced){ |
| NodeTraits::set_left(temp, new_node); |
| } |
| if(NodeTraits::get_right(temp) == node_to_be_replaced){ |
| NodeTraits::set_right(temp, 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) |
| { |
| node_ptr p_right(NodeTraits::get_right(p)); |
| if(p_right){ |
| return minimum(p_right); |
| } |
| else { |
| node_ptr x = NodeTraits::get_parent(p); |
| while(p == NodeTraits::get_right(x)){ |
| p = x; |
| x = NodeTraits::get_parent(x); |
| } |
| return NodeTraits::get_right(p) != x ? x : uncast(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) |
| { |
| if(is_header(p)){ |
| return NodeTraits::get_right(p); |
| //return maximum(NodeTraits::get_parent(p)); |
| } |
| else if(NodeTraits::get_left(p)){ |
| return maximum(NodeTraits::get_left(p)); |
| } |
| else { |
| node_ptr x = NodeTraits::get_parent(p); |
| while(p == NodeTraits::get_left(x)){ |
| p = x; |
| x = NodeTraits::get_parent(x); |
| } |
| return x; |
| } |
| } |
| |
| //! <b>Requires</b>: p is a node of a tree but not the header. |
| //! |
| //! <b>Effects</b>: Returns the minimum node of the subtree starting at p. |
| //! |
| //! <b>Complexity</b>: Logarithmic to the size of the subtree. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static node_ptr minimum (node_ptr p) |
| { |
| for(node_ptr p_left = NodeTraits::get_left(p) |
| ;p_left |
| ;p_left = NodeTraits::get_left(p)){ |
| p = p_left; |
| } |
| return p; |
| } |
| |
| //! <b>Requires</b>: p is a node of a tree but not the header. |
| //! |
| //! <b>Effects</b>: Returns the maximum node of the subtree starting at p. |
| //! |
| //! <b>Complexity</b>: Logarithmic to the size of the subtree. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static node_ptr maximum(node_ptr p) |
| { |
| for(node_ptr p_right = NodeTraits::get_right(p) |
| ;p_right |
| ;p_right = NodeTraits::get_right(p)){ |
| p = p_right; |
| } |
| return 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) |
| { |
| NodeTraits::set_parent(node, node_ptr(0)); |
| NodeTraits::set_left(node, node_ptr(0)); |
| NodeTraits::set_right(node, node_ptr(0)); |
| }; |
| |
| //! <b>Effects</b>: Returns true if node is in the same state as if called init(node) |
| //! |
| //! <b>Complexity</b>: Constant. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static bool inited(const_node_ptr node) |
| { |
| return !NodeTraits::get_parent(node) && |
| !NodeTraits::get_left(node) && |
| !NodeTraits::get_right(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) |
| { |
| NodeTraits::set_parent(header, node_ptr(0)); |
| NodeTraits::set_left(header, header); |
| NodeTraits::set_right(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) |
| { |
| node_ptr source_root = NodeTraits::get_parent(header); |
| if(!source_root) |
| return; |
| dispose_subtree(source_root, disposer); |
| init_header(header); |
| } |
| |
| //! <b>Requires</b>: header is the header of a tree. |
| //! |
| //! <b>Effects</b>: Unlinks the leftmost node from the tree, and |
| //! updates the header link to the new leftmost node. |
| //! |
| //! <b>Complexity</b>: Average complexity is constant time. |
| //! |
| //! <b>Throws</b>: Nothing. |
| //! |
| //! <b>Notes</b>: This function breaks the tree and the tree can |
| //! only be used for more unlink_leftmost_without_rebalance calls. |
| //! This function is normally used to achieve a step by step |
| //! controlled destruction of the tree. |
| static node_ptr unlink_leftmost_without_rebalance(node_ptr header) |
| { |
| node_ptr leftmost = NodeTraits::get_left(header); |
| if (leftmost == header) |
| return node_ptr(0); |
| node_ptr leftmost_parent(NodeTraits::get_parent(leftmost)); |
| node_ptr leftmost_right (NodeTraits::get_right(leftmost)); |
| bool is_root = leftmost_parent == header; |
| |
| if (leftmost_right){ |
| NodeTraits::set_parent(leftmost_right, leftmost_parent); |
| NodeTraits::set_left(header, tree_algorithms::minimum(leftmost_right)); |
| |
| if (is_root) |
| NodeTraits::set_parent(header, leftmost_right); |
| else |
| NodeTraits::set_left(NodeTraits::get_parent(header), leftmost_right); |
| } |
| else if (is_root){ |
| NodeTraits::set_parent(header, node_ptr(0)); |
| NodeTraits::set_left(header, header); |
| NodeTraits::set_right(header, header); |
| } |
| else{ |
| NodeTraits::set_left(leftmost_parent, node_ptr(0)); |
| NodeTraits::set_left(header, leftmost_parent); |
| } |
| return leftmost; |
| } |
| |
| //! <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 subtree) |
| { |
| if(!subtree) return 0; |
| std::size_t count = 0; |
| node_ptr p = minimum(uncast(subtree)); |
| bool continue_looping = true; |
| while(continue_looping){ |
| ++count; |
| node_ptr p_right(NodeTraits::get_right(p)); |
| if(p_right){ |
| p = minimum(p_right); |
| } |
| else { |
| for(;;){ |
| node_ptr q; |
| if (p == subtree){ |
| continue_looping = false; |
| break; |
| } |
| q = p; |
| p = NodeTraits::get_parent(p); |
| if (NodeTraits::get_left(p) == q) |
| break; |
| } |
| } |
| } |
| return count; |
| } |
| |
| //! <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 size(const_node_ptr header) |
| { |
| node_ptr beg(begin_node(header)); |
| node_ptr end(end_node(header)); |
| std::size_t i = 0; |
| for(;beg != end; beg = next_node(beg)) ++i; |
| return i; |
| } |
| |
| //! <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) |
| { |
| if(header1 == header2) |
| return; |
| |
| node_ptr tmp; |
| |
| //Parent swap |
| tmp = NodeTraits::get_parent(header1); |
| NodeTraits::set_parent(header1, NodeTraits::get_parent(header2)); |
| NodeTraits::set_parent(header2, tmp); |
| //Left swap |
| tmp = NodeTraits::get_left(header1); |
| NodeTraits::set_left(header1, NodeTraits::get_left(header2)); |
| NodeTraits::set_left(header2, tmp); |
| //Right swap |
| tmp = NodeTraits::get_right(header1); |
| NodeTraits::set_right(header1, NodeTraits::get_right(header2)); |
| NodeTraits::set_right(header2, tmp); |
| |
| //Now test parent |
| node_ptr h1_parent(NodeTraits::get_parent(header1)); |
| if(h1_parent){ |
| NodeTraits::set_parent(h1_parent, header1); |
| } |
| else{ |
| NodeTraits::set_left(header1, header1); |
| NodeTraits::set_right(header1, header1); |
| } |
| |
| node_ptr h2_parent(NodeTraits::get_parent(header2)); |
| if(h2_parent){ |
| NodeTraits::set_parent(h2_parent, header2); |
| } |
| else{ |
| NodeTraits::set_left(header2, header2); |
| NodeTraits::set_right(header2, header2); |
| } |
| } |
| |
| static bool is_header(const_node_ptr p) |
| { |
| node_ptr p_left (NodeTraits::get_left(p)); |
| node_ptr p_right(NodeTraits::get_right(p)); |
| if(!NodeTraits::get_parent(p) || //Header condition when empty tree |
| (p_left && p_right && //Header always has leftmost and rightmost |
| (p_left == p_right || //Header condition when only node |
| (NodeTraits::get_parent(p_left) != p || |
| NodeTraits::get_parent(p_right) != p )) |
| //When tree size > 1 headers can't be leftmost's |
| //and rightmost's parent |
| )){ |
| return true; |
| } |
| return false; |
| } |
| |
| //! <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) |
| { |
| node_ptr end = uncast(header); |
| node_ptr y = lower_bound(header, key, comp); |
| return (y == end || comp(key, y)) ? end : 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 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) |
| { |
| node_ptr y = uncast(header); |
| node_ptr x = NodeTraits::get_parent(header); |
| |
| while(x){ |
| if(comp(x, key)){ |
| x = NodeTraits::get_right(x); |
| } |
| else if(comp(key, x)){ |
| y = x; |
| x = NodeTraits::get_left(x); |
| } |
| else{ |
| node_ptr xu(x), yu(y); |
| y = x, x = NodeTraits::get_left(x); |
| xu = NodeTraits::get_right(xu); |
| |
| while(x){ |
| if(comp(x, key)){ |
| x = NodeTraits::get_right(x); |
| } |
| else { |
| y = x; |
| x = NodeTraits::get_left(x); |
| } |
| } |
| |
| while(xu){ |
| if(comp(key, xu)){ |
| yu = xu; |
| xu = NodeTraits::get_left(xu); |
| } |
| else { |
| xu = NodeTraits::get_right(xu); |
| } |
| } |
| return std::pair<node_ptr,node_ptr> (y, yu); |
| } |
| } |
| return std::pair<node_ptr,node_ptr> (y, 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 |
| //! 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) |
| { |
| node_ptr y = uncast(header); |
| node_ptr x = NodeTraits::get_parent(header); |
| while(x){ |
| if(comp(x, key)){ |
| x = NodeTraits::get_right(x); |
| } |
| else { |
| y = x; |
| x = NodeTraits::get_left(x); |
| } |
| } |
| 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) |
| { |
| node_ptr y = uncast(header); |
| node_ptr x = NodeTraits::get_parent(header); |
| while(x){ |
| if(comp(key, x)){ |
| y = x; |
| x = NodeTraits::get_left(x); |
| } |
| else { |
| x = NodeTraits::get_right(x); |
| } |
| } |
| return y; |
| } |
| |
| //! <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) |
| { return insert_commit(header, new_value, commit_data); } |
| |
| static void insert_commit |
| (node_ptr header, node_ptr new_node, const insert_commit_data &commit_data) |
| { |
| //Check if commit_data has not been initialized by a insert_unique_check call. |
| BOOST_INTRUSIVE_INVARIANT_ASSERT(commit_data.node != 0); |
| node_ptr parent_node(commit_data.node); |
| if(parent_node == header){ |
| NodeTraits::set_parent(header, new_node); |
| NodeTraits::set_right(header, new_node); |
| NodeTraits::set_left(header, new_node); |
| } |
| else if(commit_data.link_left){ |
| NodeTraits::set_left(parent_node, new_node); |
| if(parent_node == NodeTraits::get_left(header)) |
| NodeTraits::set_left(header, new_node); |
| } |
| else{ |
| NodeTraits::set_right(parent_node, new_node); |
| if(parent_node == NodeTraits::get_right(header)) |
| NodeTraits::set_right(header, new_node); |
| } |
| NodeTraits::set_parent(new_node, parent_node); |
| NodeTraits::set_right(new_node, node_ptr(0)); |
| NodeTraits::set_left(new_node, node_ptr(0)); |
| } |
| |
| //! <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 |
| (const_node_ptr header, const KeyType &key |
| ,KeyNodePtrCompare comp, insert_commit_data &commit_data, std::size_t *pdepth = 0) |
| { |
| std::size_t depth = 0; |
| node_ptr h(uncast(header)); |
| node_ptr y(h); |
| node_ptr x(NodeTraits::get_parent(y)); |
| node_ptr prev(0); |
| |
| //Find the upper bound, cache the previous value and if we should |
| //store it in the left or right node |
| bool left_child = true; |
| while(x){ |
| ++depth; |
| y = x; |
| x = (left_child = comp(key, x)) ? |
| NodeTraits::get_left(x) : (prev = y, NodeTraits::get_right(x)); |
| } |
| |
| if(pdepth) *pdepth = depth; |
| |
| //Since we've found the upper bound there is no other value with the same key if: |
| // - There is no previous node |
| // - The previous node is less than the key |
| if(!prev || comp(prev, key)){ |
| commit_data.link_left = left_child; |
| commit_data.node = y; |
| return std::pair<node_ptr, bool>(node_ptr(), true); |
| } |
| //If the previous value was not less than key, it means that it's equal |
| //(because we've checked the upper bound) |
| else{ |
| return std::pair<node_ptr, bool>(prev, false); |
| } |
| } |
| |
| template<class KeyType, class KeyNodePtrCompare> |
| static std::pair<node_ptr, bool> insert_unique_check |
| (const_node_ptr header, node_ptr hint, const KeyType &key |
| ,KeyNodePtrCompare comp, insert_commit_data &commit_data, std::size_t *pdepth = 0) |
| { |
| //hint must be bigger than the key |
| if(hint == header || comp(key, hint)){ |
| node_ptr prev(hint); |
| //Previous value should be less than the key |
| if(hint == begin_node(header)|| comp((prev = prev_node(hint)), key)){ |
| commit_data.link_left = unique(header) || !NodeTraits::get_left(hint); |
| commit_data.node = commit_data.link_left ? hint : prev; |
| if(pdepth){ |
| *pdepth = commit_data.node == header ? 0 : depth(commit_data.node) + 1; |
| } |
| return std::pair<node_ptr, bool>(node_ptr(), true); |
| } |
| } |
| //Hint was wrong, use hintless insertion |
| return insert_unique_check(header, key, comp, commit_data, pdepth); |
| } |
| |
| template<class NodePtrCompare> |
| static void insert_equal_check |
| ( node_ptr header, node_ptr hint, node_ptr new_node, NodePtrCompare comp |
| , insert_commit_data &commit_data, std::size_t *pdepth = 0) |
| { |
| if(hint == header || !comp(hint, new_node)){ |
| node_ptr prev(hint); |
| if(hint == NodeTraits::get_left(header) || |
| !comp(new_node, (prev = prev_node(hint)))){ |
| bool link_left = unique(header) || !NodeTraits::get_left(hint); |
| commit_data.link_left = link_left; |
| commit_data.node = link_left ? hint : prev; |
| if(pdepth){ |
| *pdepth = commit_data.node == header ? 0 : depth(commit_data.node) + 1; |
| } |
| } |
| else{ |
| insert_equal_upper_bound_check(header, new_node, comp, commit_data, pdepth); |
| } |
| } |
| else{ |
| insert_equal_lower_bound_check(header, new_node, comp, commit_data, pdepth); |
| } |
| } |
| |
| template<class NodePtrCompare> |
| static void insert_equal_upper_bound_check |
| (node_ptr h, node_ptr new_node, NodePtrCompare comp, insert_commit_data & commit_data, std::size_t *pdepth = 0) |
| { insert_equal_check_impl(true, h, new_node, comp, commit_data, pdepth); } |
| |
| template<class NodePtrCompare> |
| static void insert_equal_lower_bound_check |
| (node_ptr h, node_ptr new_node, NodePtrCompare comp, insert_commit_data & commit_data, std::size_t *pdepth = 0) |
| { insert_equal_check_impl(false, h, new_node, comp, commit_data, pdepth); } |
| |
| template<class NodePtrCompare> |
| static node_ptr insert_equal |
| (node_ptr h, node_ptr hint, node_ptr new_node, NodePtrCompare comp, std::size_t *pdepth = 0) |
| { |
| insert_commit_data commit_data; |
| insert_equal_check(h, hint, new_node, comp, commit_data, pdepth); |
| insert_commit(h, new_node, commit_data); |
| return new_node; |
| } |
| |
| template<class NodePtrCompare> |
| static node_ptr insert_equal_upper_bound |
| (node_ptr h, node_ptr new_node, NodePtrCompare comp, std::size_t *pdepth = 0) |
| { |
| insert_commit_data commit_data; |
| insert_equal_upper_bound_check(h, new_node, comp, commit_data, pdepth); |
| insert_commit(h, new_node, commit_data); |
| return new_node; |
| } |
| |
| template<class NodePtrCompare> |
| static node_ptr insert_equal_lower_bound |
| (node_ptr h, node_ptr new_node, NodePtrCompare comp, std::size_t *pdepth = 0) |
| { |
| insert_commit_data commit_data; |
| insert_equal_lower_bound_check(h, new_node, comp, commit_data, pdepth); |
| insert_commit(h, new_node, commit_data); |
| return new_node; |
| } |
| |
| static node_ptr insert_before |
| (node_ptr header, node_ptr pos, node_ptr new_node, std::size_t *pdepth = 0) |
| { |
| insert_commit_data commit_data; |
| insert_before_check(header, pos, commit_data, pdepth); |
| insert_commit(header, new_node, commit_data); |
| return new_node; |
| } |
| |
| static void insert_before_check |
| ( node_ptr header, node_ptr pos |
| , insert_commit_data &commit_data, std::size_t *pdepth = 0) |
| { |
| node_ptr prev(pos); |
| if(pos != NodeTraits::get_left(header)) |
| prev = prev_node(pos); |
| bool link_left = unique(header) || !NodeTraits::get_left(pos); |
| commit_data.link_left = link_left; |
| commit_data.node = link_left ? pos : prev; |
| if(pdepth){ |
| *pdepth = commit_data.node == header ? 0 : depth(commit_data.node) + 1; |
| } |
| } |
| |
| static void push_back |
| (node_ptr header, node_ptr new_node, std::size_t *pdepth = 0) |
| { |
| insert_commit_data commit_data; |
| push_back_check(header, commit_data, pdepth); |
| insert_commit(header, new_node, commit_data); |
| } |
| |
| static void push_back_check |
| (node_ptr header, insert_commit_data &commit_data, std::size_t *pdepth = 0) |
| { |
| node_ptr prev(NodeTraits::get_right(header)); |
| if(pdepth){ |
| *pdepth = prev == header ? 0 : depth(prev) + 1; |
| } |
| commit_data.link_left = false; |
| commit_data.node = prev; |
| } |
| |
| static void push_front |
| (node_ptr header, node_ptr new_node, std::size_t *pdepth = 0) |
| { |
| insert_commit_data commit_data; |
| push_front_check(header, commit_data, pdepth); |
| insert_commit(header, new_node, commit_data); |
| } |
| |
| static void push_front_check |
| (node_ptr header, insert_commit_data &commit_data, std::size_t *pdepth = 0) |
| { |
| node_ptr pos(NodeTraits::get_left(header)); |
| if(pdepth){ |
| *pdepth = pos == header ? 0 : depth(pos) + 1; |
| } |
| commit_data.link_left = true; |
| commit_data.node = pos; |
| } |
| |
| //! <b>Requires</b>: p can't be a header node. |
| //! |
| //! <b>Effects</b>: Calculates the depth of a node: the depth of a |
| //! node is the length (number of edges) of the path from the root |
| //! to that node. (The root node is at depth 0.) |
| //! |
| //! <b>Complexity</b>: Logarithmic to the number of nodes in the tree. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static std::size_t depth(const_node_ptr p) |
| { |
| std::size_t depth = 0; |
| node_ptr p_parent; |
| while(p != NodeTraits::get_parent(p_parent = NodeTraits::get_parent(p))){ |
| ++depth; |
| p = p_parent; |
| } |
| return depth; |
| } |
| |
| //! <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) |
| { |
| if(!unique(target_header)){ |
| clear_and_dispose(target_header, disposer); |
| } |
| |
| node_ptr leftmost, rightmost; |
| node_ptr new_root = clone_subtree |
| (source_header, target_header, cloner, disposer, leftmost, rightmost); |
| |
| //Now update header node |
| NodeTraits::set_parent(target_header, new_root); |
| NodeTraits::set_left (target_header, leftmost); |
| NodeTraits::set_right (target_header, rightmost); |
| } |
| |
| template <class Cloner, class Disposer> |
| static node_ptr clone_subtree |
| ( const_node_ptr source_parent, node_ptr target_parent |
| , Cloner cloner, Disposer disposer |
| , node_ptr &leftmost_out, node_ptr &rightmost_out |
| ) |
| { |
| node_ptr target_sub_root = target_parent; |
| node_ptr source_root = NodeTraits::get_parent(source_parent); |
| if(!source_root){ |
| leftmost_out = rightmost_out = source_root; |
| } |
| else{ |
| //We'll calculate leftmost and rightmost nodes while iterating |
| node_ptr current = source_root; |
| node_ptr insertion_point = target_sub_root = cloner(current); |
| |
| //We'll calculate leftmost and rightmost nodes while iterating |
| node_ptr leftmost = target_sub_root; |
| node_ptr rightmost = target_sub_root; |
| |
| //First set the subroot |
| NodeTraits::set_left(target_sub_root, node_ptr(0)); |
| NodeTraits::set_right(target_sub_root, node_ptr(0)); |
| NodeTraits::set_parent(target_sub_root, target_parent); |
| |
| dispose_subtree_disposer<Disposer> rollback(disposer, target_sub_root); |
| while(true) { |
| //First clone left nodes |
| if( NodeTraits::get_left(current) && |
| !NodeTraits::get_left(insertion_point)) { |
| current = NodeTraits::get_left(current); |
| node_ptr temp = insertion_point; |
| //Clone and mark as leaf |
| insertion_point = cloner(current); |
| NodeTraits::set_left (insertion_point, node_ptr(0)); |
| NodeTraits::set_right (insertion_point, node_ptr(0)); |
| //Insert left |
| NodeTraits::set_parent(insertion_point, temp); |
| NodeTraits::set_left (temp, insertion_point); |
| //Update leftmost |
| if(rightmost == target_sub_root) |
| leftmost = insertion_point; |
| } |
| //Then clone right nodes |
| else if( NodeTraits::get_right(current) && |
| !NodeTraits::get_right(insertion_point)){ |
| current = NodeTraits::get_right(current); |
| node_ptr temp = insertion_point; |
| //Clone and mark as leaf |
| insertion_point = cloner(current); |
| NodeTraits::set_left (insertion_point, node_ptr(0)); |
| NodeTraits::set_right (insertion_point, node_ptr(0)); |
| //Insert right |
| NodeTraits::set_parent(insertion_point, temp); |
| NodeTraits::set_right (temp, insertion_point); |
| //Update rightmost |
| rightmost = insertion_point; |
| } |
| //If not, go up |
| else if(current == source_root){ |
| break; |
| } |
| else{ |
| //Branch completed, go up searching more nodes to clone |
| current = NodeTraits::get_parent(current); |
| insertion_point = NodeTraits::get_parent(insertion_point); |
| } |
| } |
| rollback.release(); |
| leftmost_out = leftmost; |
| rightmost_out = rightmost; |
| } |
| return target_sub_root; |
| } |
| |
| template<class Disposer> |
| static void dispose_subtree(node_ptr x, Disposer disposer) |
| { |
| node_ptr save; |
| while (x){ |
| save = NodeTraits::get_left(x); |
| if (save) { |
| // Right rotation |
| NodeTraits::set_left(x, NodeTraits::get_right(save)); |
| NodeTraits::set_right(save, x); |
| } |
| else { |
| save = NodeTraits::get_right(x); |
| init(x); |
| disposer(x); |
| } |
| x = save; |
| } |
| } |
| |
| //! <b>Requires</b>: p is a node of a tree. |
| //! |
| //! <b>Effects</b>: Returns true if p is a left child. |
| //! |
| //! <b>Complexity</b>: Constant. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static bool is_left_child(node_ptr p) |
| { return NodeTraits::get_left(NodeTraits::get_parent(p)) == p; } |
| |
| //! <b>Requires</b>: p is a node of a tree. |
| //! |
| //! <b>Effects</b>: Returns true if p is a right child. |
| //! |
| //! <b>Complexity</b>: Constant. |
| //! |
| //! <b>Throws</b>: Nothing. |
| static bool is_right_child(node_ptr p) |
| { return NodeTraits::get_right(NodeTraits::get_parent(p)) == p; } |
| |
| //Fix header and own's parent data when replacing x with own, providing own's old data with parent |
| static void replace_own_impl(node_ptr own, node_ptr x, node_ptr header, node_ptr own_parent, bool own_was_left) |
| { |
| if(NodeTraits::get_parent(header) == own) |
| NodeTraits::set_parent(header, x); |
| else if(own_was_left) |
| NodeTraits::set_left(own_parent, x); |
| else |
| NodeTraits::set_right(own_parent, x); |
| } |
| |
| //Fix header and own's parent data when replacing x with own, supposing own |
| //links with its parent are still ok |
| static void replace_own(node_ptr own, node_ptr x, node_ptr header) |
| { |
| node_ptr own_parent(NodeTraits::get_parent(own)); |
| bool own_is_left(NodeTraits::get_left(own_parent) == own); |
| replace_own_impl(own, x, header, own_parent, own_is_left); |
| } |
| |
| // rotate parent p to left (no header and p's parent fixup) |
| static node_ptr rotate_left(node_ptr p) |
| { |
| node_ptr x(NodeTraits::get_right(p)); |
| node_ptr x_left(NodeTraits::get_left(x)); |
| NodeTraits::set_right(p, x_left); |
| if(x_left){ |
| NodeTraits::set_parent(x_left, p); |
| } |
| NodeTraits::set_left(x, p); |
| NodeTraits::set_parent(p, x); |
| return x; |
| } |
| |
| // rotate parent p to left (with header and p's parent fixup) |
| static void rotate_left(node_ptr p, node_ptr header) |
| { |
| bool p_was_left(is_left_child(p)); |
| node_ptr p_old_parent(NodeTraits::get_parent(p)); |
| node_ptr x(rotate_left(p)); |
| NodeTraits::set_parent(x, p_old_parent); |
| replace_own_impl(p, x, header, p_old_parent, p_was_left); |
| } |
| |
| // rotate parent p to right (no header and p's parent fixup) |
| static node_ptr rotate_right(node_ptr p) |
| { |
| node_ptr x(NodeTraits::get_left(p)); |
| node_ptr x_right(NodeTraits::get_right(x)); |
| NodeTraits::set_left(p, x_right); |
| if(x_right){ |
| NodeTraits::set_parent(x_right, p); |
| } |
| NodeTraits::set_right(x, p); |
| NodeTraits::set_parent(p, x); |
| return x; |
| } |
| |
| // rotate parent p to right (with header and p's parent fixup) |
| static void rotate_right(node_ptr p, node_ptr header) |
| { |
| bool p_was_left(is_left_child(p)); |
| node_ptr p_old_parent(NodeTraits::get_parent(p)); |
| node_ptr x(rotate_right(p)); |
| NodeTraits::set_parent(x, p_old_parent); |
| replace_own_impl(p, x, header, p_old_parent, p_was_left); |
| } |
| |
| static void erase(node_ptr header, node_ptr z) |
| { |
| data_for_rebalance ignored; |
| erase_impl(header, z, ignored); |
| } |
| |
| struct data_for_rebalance |
| { |
| node_ptr x; |
| node_ptr x_parent; |
| node_ptr y; |
| }; |
| |
| template<class F> |
| static void erase(node_ptr header, node_ptr z, F z_and_successor_fixup, data_for_rebalance &info) |
| { |
| erase_impl(header, z, info); |
| if(info.y != z){ |
| z_and_successor_fixup(z, info.y); |
| } |
| } |
| |
| static void unlink(node_ptr node) |
| { |
| node_ptr x = NodeTraits::get_parent(node); |
| if(x){ |
| while(!is_header(x)) |
| x = NodeTraits::get_parent(x); |
| erase(x, node); |
| } |
| } |
| |
| static void tree_to_vine(node_ptr header) |
| { subtree_to_vine(NodeTraits::get_parent(header)); } |
| |
| static void vine_to_tree(node_ptr header, std::size_t count) |
| { vine_to_subtree(NodeTraits::get_parent(header), count); } |
| |
| static void rebalance(node_ptr header) |
| { |
| //Taken from: |
| //"Tree rebalancing in optimal time and space" |
| //Quentin F. Stout and Bette L. Warren |
| std::size_t len = 0; |
| subtree_to_vine(NodeTraits::get_parent(header), &len); |
| vine_to_subtree(NodeTraits::get_parent(header), len); |
| } |
| |
| static node_ptr rebalance_subtree(node_ptr old_root) |
| { |
| std::size_t len = 0; |
| node_ptr new_root = subtree_to_vine(old_root, &len); |
| return vine_to_subtree(new_root, len); |
| } |
| |
| static node_ptr subtree_to_vine(node_ptr old_root, std::size_t *plen = 0) |
| { |
| std::size_t len; |
| len = 0; |
| if(!old_root) return node_ptr(0); |
| |
| //To avoid irregularities in the algorithm (old_root can be a |
| //left or right child or even the root of the tree) just put the |
| //root as the right child of its parent. Before doing this backup |
| //information to restore the original relationship after |
| //the algorithm is applied. |
| node_ptr super_root = NodeTraits::get_parent(old_root); |
| BOOST_INTRUSIVE_INVARIANT_ASSERT(super_root); |
| |
| //Get info |
| node_ptr super_root_right_backup = NodeTraits::get_right(super_root); |
| bool super_root_is_header = is_header(super_root); |
| bool old_root_is_right = is_right_child(old_root); |
| |
| node_ptr x(old_root); |
| node_ptr new_root(x); |
| node_ptr save; |
| bool moved_to_right = false; |
| for( ; x; x = save){ |
| save = NodeTraits::get_left(x); |
| if(save){ |
| // Right rotation |
| node_ptr save_right = NodeTraits::get_right(save); |
| node_ptr x_parent = NodeTraits::get_parent(x); |
| NodeTraits::set_parent(save, x_parent); |
| NodeTraits::set_right (x_parent, save); |
| NodeTraits::set_parent(x, save); |
| NodeTraits::set_right (save, x); |
| NodeTraits::set_left(x, save_right); |
| if(save_right) |
| NodeTraits::set_parent(save_right, x); |
| if(!moved_to_right) |
| new_root = save; |
| } |
| else{ |
| moved_to_right = true; |
| save = NodeTraits::get_right(x); |
| ++len; |
| } |
| } |
| |
| if(super_root_is_header){ |
| NodeTraits::set_right(super_root, super_root_right_backup); |
| NodeTraits::set_parent(super_root, new_root); |
| } |
| else if(old_root_is_right){ |
| NodeTraits::set_right(super_root, new_root); |
| } |
| else{ |
| NodeTraits::set_right(super_root, super_root_right_backup); |
| NodeTraits::set_left(super_root, new_root); |
| } |
| if(plen) *plen = len; |
| return new_root; |
| } |
| |
| static node_ptr vine_to_subtree(node_ptr old_root, std::size_t count) |
| { |
| std::size_t leaf_nodes = count + 1 - ((std::size_t) 1 << floor_log2 (count + 1)); |
| std::size_t vine_nodes = count - leaf_nodes; |
| |
| node_ptr new_root = compress_subtree(old_root, leaf_nodes); |
| while(vine_nodes > 1){ |
| vine_nodes /= 2; |
| new_root = compress_subtree(new_root, vine_nodes); |
| } |
| return new_root; |
| } |
| |
| static node_ptr compress_subtree(node_ptr old_root, std::size_t count) |
| { |
| if(!old_root) return old_root; |
| |
| //To avoid irregularities in the algorithm (old_root can be |
| //left or right child or even the root of the tree) just put the |
| //root as the right child of its parent. First obtain |
| //information to restore the original relationship after |
| //the algorithm is applied. |
| node_ptr super_root = NodeTraits::get_parent(old_root); |
| BOOST_INTRUSIVE_INVARIANT_ASSERT(super_root); |
| |
| //Get info |
| node_ptr super_root_right_backup = NodeTraits::get_right(super_root); |
| bool super_root_is_header = is_header(super_root); |
| bool old_root_is_right = is_right_child(old_root); |
| |
| //Put old_root as right child |
| NodeTraits::set_right(super_root, old_root); |
| |
| //Start the compression algorithm |
| node_ptr even_parent = super_root; |
| node_ptr new_root = old_root; |
| |
| while(count--){ |
| node_ptr even = NodeTraits::get_right(even_parent); |
| node_ptr odd = NodeTraits::get_right(even); |
| |
| if(new_root == old_root) |
| new_root = odd; |
| |
| node_ptr even_right = NodeTraits::get_left(odd); |
| NodeTraits::set_right(even, even_right); |
| if (even_right) |
| NodeTraits::set_parent(even_right, even); |
| |
| NodeTraits::set_right(even_parent, odd); |
| NodeTraits::set_parent(odd, even_parent); |
| NodeTraits::set_left(odd, even); |
| NodeTraits::set_parent(even, odd); |
| even_parent = odd; |
| } |
| |
| if(super_root_is_header){ |
| NodeTraits::set_parent(super_root, new_root); |
| NodeTraits::set_right(super_root, super_root_right_backup); |
| } |
| else if(old_root_is_right){ |
| NodeTraits::set_right(super_root, new_root); |
| } |
| else{ |
| NodeTraits::set_left(super_root, new_root); |
| NodeTraits::set_right(super_root, super_root_right_backup); |
| } |
| return new_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_root(node_ptr node) |
| { |
| BOOST_INTRUSIVE_INVARIANT_ASSERT((!inited(node))); |
| node_ptr x = NodeTraits::get_parent(node); |
| if(x){ |
| while(!is_header(x)){ |
| x = NodeTraits::get_parent(x); |
| } |
| return x; |
| } |
| else{ |
| return node; |
| } |
| } |
| |
| private: |
| template<class NodePtrCompare> |
| static void insert_equal_check_impl |
| (bool upper, node_ptr h, node_ptr new_node, NodePtrCompare comp, insert_commit_data & commit_data, std::size_t *pdepth = 0) |
| { |
| std::size_t depth = 0; |
| node_ptr y(h); |
| node_ptr x(NodeTraits::get_parent(y)); |
| bool link_left; |
| |
| if(upper){ |
| while(x){ |
| ++depth; |
| y = x; |
| x = comp(new_node, x) ? |
| NodeTraits::get_left(x) : NodeTraits::get_right(x); |
| } |
| link_left = (y == h) || comp(new_node, y); |
| } |
| else{ |
| while(x){ |
| ++depth; |
| y = x; |
| x = !comp(x, new_node) ? |
| NodeTraits::get_left(x) : NodeTraits::get_right(x); |
| } |
| link_left = (y == h) || !comp(y, new_node); |
| } |
| |
| commit_data.link_left = link_left; |
| commit_data.node = y; |
| if(pdepth) *pdepth = depth; |
| } |
| |
| static void erase_impl(node_ptr header, node_ptr z, data_for_rebalance &info) |
| { |
| node_ptr y(z); |
| node_ptr x; |
| node_ptr x_parent(0); |
| node_ptr z_left(NodeTraits::get_left(z)); |
| node_ptr z_right(NodeTraits::get_right(z)); |
| if(!z_left){ |
| x = z_right; // x might be null. |
| } |
| else if(!z_right){ // z has exactly one non-null child. y == z. |
| x = z_left; // x is not null. |
| } |
| else{ |
| // find z's successor |
| y = tree_algorithms::minimum (z_right); |
| x = NodeTraits::get_right(y); // x might be null. |
| } |
| |
| if(y != z){ |
| // relink y in place of z. y is z's successor |
| NodeTraits::set_parent(NodeTraits::get_left(z), y); |
| NodeTraits::set_left(y, NodeTraits::get_left(z)); |
| if(y != NodeTraits::get_right(z)){ |
| x_parent = NodeTraits::get_parent(y); |
| if(x) |
| NodeTraits::set_parent(x, x_parent); |
| NodeTraits::set_left(x_parent, x); // y must be a child of left_ |
| NodeTraits::set_right(y, NodeTraits::get_right(z)); |
| NodeTraits::set_parent(NodeTraits::get_right(z), y); |
| } |
| else |
| x_parent = y; |
| tree_algorithms::replace_own (z, y, header); |
| NodeTraits::set_parent(y, NodeTraits::get_parent(z)); |
| } |
| else { // y == z --> z has only one child, or none |
| x_parent = NodeTraits::get_parent(z); |
| if(x) |
| NodeTraits::set_parent(x, x_parent); |
| tree_algorithms::replace_own (z, x, header); |
| if(NodeTraits::get_left(header) == z){ |
| NodeTraits::set_left(header, !NodeTraits::get_right(z) ? // z->get_left() must be null also |
| NodeTraits::get_parent(z) : // makes leftmost == header if z == root |
| tree_algorithms::minimum (x)); |
| } |
| if(NodeTraits::get_right(header) == z){ |
| NodeTraits::set_right(header, !NodeTraits::get_left(z) ? // z->get_right() must be null also |
| NodeTraits::get_parent(z) : // makes rightmost == header if z == root |
| tree_algorithms::maximum(x)); |
| } |
| } |
| |
| info.x = x; |
| info.x_parent = x_parent; |
| info.y = y; |
| } |
| }; |
| |
| } //namespace detail { |
| } //namespace intrusive |
| } //namespace boost |
| |
| #include <boost/intrusive/detail/config_end.hpp> |
| |
| #endif //BOOST_INTRUSIVE_TREE_ALGORITHMS_HPP |