684 lines
27 KiB
C++
684 lines
27 KiB
C++
/////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// (C) Copyright Ion Gaztanaga 2007-2013
|
|
//
|
|
// 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 splay code has been modified and (supposedly) improved by Ion Gaztanaga.
|
|
//
|
|
// Here is the copyright notice of the original file containing the splay code:
|
|
//
|
|
// splay_tree.h -- implementation of a STL compatible 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.
|
|
//
|
|
/////////////////////////////////////////////////////////////////////////////
|
|
|
|
#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 <boost/intrusive/pointer_traits.hpp>
|
|
#include <cstddef>
|
|
#include <boost/intrusive/detail/utilities.hpp>
|
|
#include <boost/intrusive/bstree_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, const node_ptr & header
|
|
, const node_ptr & leftmost , const 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 binary search tree
|
|
//!
|
|
//! <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
|
|
#ifndef BOOST_INTRUSIVE_DOXYGEN_INVOKED
|
|
: public bstree_algorithms<NodeTraits>
|
|
#endif
|
|
{
|
|
/// @cond
|
|
private:
|
|
typedef bstree_algorithms<NodeTraits> bstree_algo;
|
|
/// @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 bstree_algo::insert_commit_data insert_commit_data;
|
|
|
|
public:
|
|
#ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::get_header(const const_node_ptr&)
|
|
static node_ptr get_header(const const_node_ptr & n);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::begin_node
|
|
static node_ptr begin_node(const const_node_ptr & header);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::end_node
|
|
static node_ptr end_node(const const_node_ptr & header);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::swap_tree
|
|
static void swap_tree(const node_ptr & header1, const node_ptr & header2);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::swap_nodes(const node_ptr&,const node_ptr&)
|
|
static void swap_nodes(const node_ptr & node1, const node_ptr & node2);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::swap_nodes(const node_ptr&,const node_ptr&,const node_ptr&,const node_ptr&)
|
|
static void swap_nodes(const node_ptr & node1, const node_ptr & header1, const node_ptr & node2, const node_ptr & header2);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::replace_node(const node_ptr&,const node_ptr&)
|
|
static void replace_node(const node_ptr & node_to_be_replaced, const node_ptr & new_node);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::replace_node(const node_ptr&,const node_ptr&,const node_ptr&)
|
|
static void replace_node(const node_ptr & node_to_be_replaced, const node_ptr & header, const node_ptr & new_node);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::unlink(const node_ptr&)
|
|
static void unlink(const node_ptr & node);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::unlink_leftmost_without_rebalance
|
|
static node_ptr unlink_leftmost_without_rebalance(const node_ptr & header);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::unique(const const_node_ptr&)
|
|
static bool unique(const const_node_ptr & node);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::size(const const_node_ptr&)
|
|
static std::size_t size(const const_node_ptr & header);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::next_node(const node_ptr&)
|
|
static node_ptr next_node(const node_ptr & node);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::prev_node(const node_ptr&)
|
|
static node_ptr prev_node(const node_ptr & node);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::init(const node_ptr&)
|
|
static void init(const node_ptr & node);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::init_header(const node_ptr&)
|
|
static void init_header(const node_ptr & header);
|
|
|
|
#endif //#ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::erase(const node_ptr&,const node_ptr&)
|
|
//! Additional notes: the previous node of z is splayed. The "splay" parameter which indicated if splaying
|
|
//! should be performed, it's deprecated and will disappear in future versions.
|
|
static void erase(const node_ptr & header, const node_ptr & z, bool splay = true)
|
|
{
|
|
//posibility 1
|
|
if(splay && NodeTraits::get_left(z)){
|
|
splay_up(bstree_algo::prev_node(z), header);
|
|
}
|
|
/*
|
|
//possibility 2
|
|
if(splay && NodeTraits::get_left(z)){
|
|
node_ptr l = NodeTraits::get_left(z);
|
|
splay_up(l, header);
|
|
}*//*
|
|
if(splay && NodeTraits::get_left(z)){
|
|
node_ptr l = bstree_algo::prev_node(z);
|
|
splay_up_impl(l, z);
|
|
}*/
|
|
/*
|
|
//possibility 4
|
|
if(splay){
|
|
splay_up(z, header);
|
|
}*/
|
|
|
|
//if(splay)
|
|
//splay_up(z, header);
|
|
bstree_algo::erase(header, z);
|
|
}
|
|
|
|
#ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::clone(const const_node_ptr&,const node_ptr&,Cloner,Disposer)
|
|
template <class Cloner, class Disposer>
|
|
static void clone
|
|
(const const_node_ptr & source_header, const node_ptr & target_header, Cloner cloner, Disposer disposer);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::clear_and_dispose(const node_ptr&,Disposer)
|
|
template<class Disposer>
|
|
static void clear_and_dispose(const node_ptr & header, Disposer disposer);
|
|
|
|
#endif //#ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::count(const const_node_ptr&,const KeyType&,KeyNodePtrCompare)
|
|
//! Additional notes: the first node of the range is splayed.
|
|
template<class KeyType, class KeyNodePtrCompare>
|
|
static std::size_t count
|
|
(const node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
|
|
{
|
|
std::pair<node_ptr, node_ptr> ret = equal_range(header, key, comp);
|
|
std::size_t n = 0;
|
|
while(ret.first != ret.second){
|
|
++n;
|
|
ret.first = next_node(ret.first);
|
|
}
|
|
return n;
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::count(const const_node_ptr&,const KeyType&,KeyNodePtrCompare)
|
|
//! Additional note: no splaying is performed
|
|
template<class KeyType, class KeyNodePtrCompare>
|
|
static std::size_t count
|
|
(const const_node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
|
|
{ return bstree_algo::count(header, key, comp); }
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::lower_bound(const const_node_ptr&,const KeyType&,KeyNodePtrCompare)
|
|
//! Additional notes: the first node of the range is splayed. The "splay" parameter which indicated if splaying
|
|
//! should be performed, it's deprecated and will disappear in future versions.
|
|
template<class KeyType, class KeyNodePtrCompare>
|
|
static node_ptr lower_bound
|
|
(const node_ptr & header, const KeyType &key, KeyNodePtrCompare comp, bool splay = true)
|
|
{
|
|
//splay_down(detail::uncast(header), key, comp);
|
|
node_ptr y = bstree_algo::lower_bound(header, key, comp);
|
|
if(splay) splay_up(y, detail::uncast(header));
|
|
return y;
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::lower_bound(const const_node_ptr&,const KeyType&,KeyNodePtrCompare)
|
|
//! Additional note: no splaying is performed
|
|
template<class KeyType, class KeyNodePtrCompare>
|
|
static node_ptr lower_bound
|
|
(const const_node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
|
|
{ return bstree_algo::lower_bound(header, key, comp); }
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::upper_bound(const const_node_ptr&,const KeyType&,KeyNodePtrCompare)
|
|
//! Additional notes: the first node of the range is splayed. The "splay" parameter which indicated if splaying
|
|
//! should be performed, it's deprecated and will disappear in future versions.
|
|
template<class KeyType, class KeyNodePtrCompare>
|
|
static node_ptr upper_bound
|
|
(const node_ptr & header, const KeyType &key, KeyNodePtrCompare comp, bool splay = true)
|
|
{
|
|
//splay_down(detail::uncast(header), key, comp);
|
|
node_ptr y = bstree_algo::upper_bound(header, key, comp);
|
|
if(splay) splay_up(y, detail::uncast(header));
|
|
return y;
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::upper_bound(const const_node_ptr&,const KeyType&,KeyNodePtrCompare)
|
|
//! Additional note: no splaying is performed
|
|
template<class KeyType, class KeyNodePtrCompare>
|
|
static node_ptr upper_bound
|
|
(const const_node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
|
|
{ return bstree_algo::upper_bound(header, key, comp); }
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::find(const const_node_ptr&, const KeyType&,KeyNodePtrCompare)
|
|
//! Additional notes: the found node of the lower bound is splayed. The "splay" parameter which indicated if splaying
|
|
//! should be performed, it's deprecated and will disappear in future versions.
|
|
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(detail::uncast(header), key, comp);
|
|
node_ptr end = detail::uncast(header);
|
|
node_ptr y = bstree_algo::lower_bound(header, key, comp);
|
|
node_ptr r = (y == end || comp(key, y)) ? end : y;
|
|
return r;
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::find(const const_node_ptr&, const KeyType&,KeyNodePtrCompare)
|
|
//! Additional note: no splaying is performed
|
|
template<class KeyType, class KeyNodePtrCompare>
|
|
static node_ptr find
|
|
(const const_node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
|
|
{ return bstree_algo::find(header, key, comp); }
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::equal_range(const const_node_ptr&,const KeyType&,KeyNodePtrCompare)
|
|
//! Additional notes: the first node of the range is splayed. The "splay" parameter which indicated if splaying
|
|
//! should be performed, it's deprecated and will disappear in future versions.
|
|
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)
|
|
{
|
|
//splay_down(detail::uncast(header), key, comp);
|
|
std::pair<node_ptr, node_ptr> ret = bstree_algo::equal_range(header, key, comp);
|
|
if(splay) splay_up(ret.first, detail::uncast(header));
|
|
return ret;
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::equal_range(const const_node_ptr&,const KeyType&,KeyNodePtrCompare)
|
|
//! Additional note: no splaying is performed
|
|
template<class KeyType, class KeyNodePtrCompare>
|
|
static std::pair<node_ptr, node_ptr> equal_range
|
|
(const const_node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
|
|
{ return bstree_algo::equal_range(header, key, comp); }
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::bounded_range(const const_node_ptr&,const KeyType&,const KeyType&,KeyNodePtrCompare,bool,bool)
|
|
//! Additional notes: the first node of the range is splayed. The "splay" parameter which indicated if splaying
|
|
//! should be performed, it's deprecated and will disappear in future versions.
|
|
template<class KeyType, class KeyNodePtrCompare>
|
|
static std::pair<node_ptr, node_ptr> bounded_range
|
|
(const node_ptr & header, const KeyType &lower_key, const KeyType &upper_key, KeyNodePtrCompare comp
|
|
, bool left_closed, bool right_closed, bool splay = true)
|
|
{
|
|
std::pair<node_ptr, node_ptr> ret =
|
|
bstree_algo::bounded_range(header, lower_key, upper_key, comp, left_closed, right_closed);
|
|
if(splay) splay_up(ret.first, detail::uncast(header));
|
|
return ret;
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::bounded_range(const const_node_ptr&,const KeyType&,const KeyType&,KeyNodePtrCompare,bool,bool)
|
|
//! Additional note: no splaying is performed
|
|
template<class KeyType, class KeyNodePtrCompare>
|
|
static std::pair<node_ptr, node_ptr> bounded_range
|
|
(const const_node_ptr & header, const KeyType &lower_key, const KeyType &upper_key, KeyNodePtrCompare comp
|
|
, bool left_closed, bool right_closed)
|
|
{ return bstree_algo::bounded_range(header, lower_key, upper_key, comp, left_closed, right_closed); }
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::insert_equal_upper_bound(const node_ptr&,const node_ptr&,NodePtrCompare)
|
|
//! Additional note: the inserted node is splayed
|
|
template<class NodePtrCompare>
|
|
static node_ptr insert_equal_upper_bound
|
|
(const node_ptr & header, const node_ptr & new_node, NodePtrCompare comp)
|
|
{
|
|
splay_down(header, new_node, comp);
|
|
return bstree_algo::insert_equal_upper_bound(header, new_node, comp);
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::insert_equal_lower_bound(const node_ptr&,const node_ptr&,NodePtrCompare)
|
|
//! Additional note: the inserted node is splayed
|
|
template<class NodePtrCompare>
|
|
static node_ptr insert_equal_lower_bound
|
|
(const node_ptr & header, const node_ptr & new_node, NodePtrCompare comp)
|
|
{
|
|
splay_down(header, new_node, comp);
|
|
return bstree_algo::insert_equal_lower_bound(header, new_node, comp);
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::insert_equal(const node_ptr&,const node_ptr&,const node_ptr&,NodePtrCompare)
|
|
//! Additional note: the inserted node is splayed
|
|
template<class NodePtrCompare>
|
|
static node_ptr insert_equal
|
|
(const node_ptr & header, const node_ptr & hint, const node_ptr & new_node, NodePtrCompare comp)
|
|
{
|
|
splay_down(header, new_node, comp);
|
|
return bstree_algo::insert_equal(header, hint, new_node, comp);
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::insert_before(const node_ptr&,const node_ptr&,const node_ptr&)
|
|
//! Additional note: the inserted node is splayed
|
|
static node_ptr insert_before
|
|
(const node_ptr & header, const node_ptr & pos, const node_ptr & new_node)
|
|
{
|
|
bstree_algo::insert_before(header, pos, new_node);
|
|
splay_up(new_node, header);
|
|
return new_node;
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::push_back(const node_ptr&,const node_ptr&)
|
|
//! Additional note: the inserted node is splayed
|
|
static void push_back(const node_ptr & header, const node_ptr & new_node)
|
|
{
|
|
bstree_algo::push_back(header, new_node);
|
|
splay_up(new_node, header);
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::push_front(const node_ptr&,const node_ptr&)
|
|
//! Additional note: the inserted node is splayed
|
|
static void push_front(const node_ptr & header, const node_ptr & new_node)
|
|
{
|
|
bstree_algo::push_front(header, new_node);
|
|
splay_up(new_node, header);
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::insert_unique_check(const const_node_ptr&,const KeyType&,KeyNodePtrCompare,insert_commit_data&)
|
|
//! Additional note: nodes with the given key are splayed
|
|
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)
|
|
{
|
|
splay_down(header, key, comp);
|
|
return bstree_algo::insert_unique_check(header, key, comp, commit_data);
|
|
}
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::insert_unique_check(const const_node_ptr&,const node_ptr&,const KeyType&,KeyNodePtrCompare,insert_commit_data&)
|
|
//! Additional note: nodes with the given key are splayed
|
|
template<class KeyType, class KeyNodePtrCompare>
|
|
static std::pair<node_ptr, bool> insert_unique_check
|
|
(const node_ptr & header, const node_ptr &hint, const KeyType &key
|
|
,KeyNodePtrCompare comp, insert_commit_data &commit_data)
|
|
{
|
|
splay_down(header, key, comp);
|
|
return bstree_algo::insert_unique_check(header, hint, key, comp, commit_data);
|
|
}
|
|
|
|
#ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::insert_unique_commit(const node_ptr&,const node_ptr&,const insert_commit_data&)
|
|
static void insert_unique_commit
|
|
(const node_ptr & header, const node_ptr & new_value, const insert_commit_data &commit_data);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::is_header
|
|
static bool is_header(const const_node_ptr & p);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::rebalance
|
|
static void rebalance(const node_ptr & header);
|
|
|
|
//! @copydoc ::boost::intrusive::bstree_algorithms::rebalance_subtree
|
|
static node_ptr rebalance_subtree(const node_ptr & old_root);
|
|
|
|
#endif //#ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED
|
|
|
|
// bottom-up splay, use data_ as parent for n | complexity : logarithmic | exception : nothrow
|
|
static void splay_up(const node_ptr & node, const node_ptr & header)
|
|
{
|
|
// If (node == 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
|
|
node_ptr n((node == header) ? NodeTraits::get_right(header) : node);
|
|
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(const 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));
|
|
{
|
|
//Anti-exception rollback, recovers the original header node if an exception is thrown.
|
|
detail::splaydown_rollback<NodeTraits> rollback(&t, header, leftmost, rightmost);
|
|
node_ptr null_node = header;
|
|
node_ptr l = null_node;
|
|
node_ptr r = null_node;
|
|
|
|
for( ;; ){
|
|
if(comp(key, t)){
|
|
if(NodeTraits::get_left(t) == node_ptr() )
|
|
break;
|
|
if(comp(key, NodeTraits::get_left(t))){
|
|
t = bstree_algo::rotate_right(t);
|
|
|
|
if(NodeTraits::get_left(t) == node_ptr())
|
|
break;
|
|
link_right(t, r);
|
|
}
|
|
else if(comp(NodeTraits::get_left(t), key)){
|
|
link_right(t, r);
|
|
|
|
if(NodeTraits::get_right(t) == node_ptr() )
|
|
break;
|
|
link_left(t, l);
|
|
}
|
|
else{
|
|
link_right(t, r);
|
|
}
|
|
}
|
|
else if(comp(t, key)){
|
|
if(NodeTraits::get_right(t) == node_ptr() )
|
|
break;
|
|
|
|
if(comp(NodeTraits::get_right(t), key)){
|
|
t = bstree_algo::rotate_left( t );
|
|
|
|
if(NodeTraits::get_right(t) == node_ptr() )
|
|
break;
|
|
link_left(t, l);
|
|
}
|
|
else if(comp(key, NodeTraits::get_right(t))){
|
|
link_left(t, l);
|
|
|
|
if(NodeTraits::get_left(t) == node_ptr())
|
|
break;
|
|
|
|
link_right(t, r);
|
|
}
|
|
else{
|
|
link_left(t, l);
|
|
}
|
|
}
|
|
else{
|
|
break;
|
|
}
|
|
}
|
|
|
|
assemble(t, l, r, null_node);
|
|
rollback.release();
|
|
}
|
|
|
|
//Now recover the original header except for the
|
|
//splayed root node.
|
|
//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;
|
|
}
|
|
|
|
private:
|
|
|
|
/// @cond
|
|
|
|
// assemble the three sub-trees into new tree pointed to by t | complexity : constant | exception : nothrow
|
|
static void assemble(const node_ptr &t, const node_ptr & l, const node_ptr & r, const 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) != node_ptr()){
|
|
NodeTraits::set_parent(NodeTraits::get_right(l), l);
|
|
}
|
|
|
|
if(NodeTraits::get_left(r) != node_ptr()){
|
|
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) != node_ptr() ){
|
|
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(const 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 = bstree_algo::is_header(g);
|
|
|
|
if(NodeTraits::get_left(p) == n){
|
|
NodeTraits::set_left(p, NodeTraits::get_right(n));
|
|
if(NodeTraits::get_left(p) != node_ptr())
|
|
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) != node_ptr())
|
|
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(false);
|
|
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
|
|
};
|
|
|
|
/// @cond
|
|
|
|
template<class NodeTraits>
|
|
struct get_algo<SplayTreeAlgorithms, NodeTraits>
|
|
{
|
|
typedef splaytree_algorithms<NodeTraits> type;
|
|
};
|
|
|
|
/// @endcond
|
|
|
|
} //namespace intrusive
|
|
} //namespace boost
|
|
|
|
#include <boost/intrusive/detail/config_end.hpp>
|
|
|
|
#endif //BOOST_INTRUSIVE_SPLAYTREE_ALGORITHMS_HPP
|