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ecency-mobile/ios/Pods/boost-for-react-native/boost/intrusive/splaytree_algorithms.hpp

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/////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2007-2014
//
// 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/intrusive_fwd.hpp>
#include <boost/intrusive/detail/assert.hpp>
#include <boost/intrusive/detail/algo_type.hpp>
#include <boost/intrusive/detail/uncast.hpp>
#include <boost/intrusive/bstree_algorithms.hpp>
#include <cstddef>
#if defined(BOOST_HAS_PRAGMA_ONCE)
# pragma once
#endif
namespace boost {
namespace intrusive {
/// @cond
namespace detail {
template<class NodeTraits>
struct splaydown_assemble_and_fix_header
{
typedef typename NodeTraits::node_ptr node_ptr;
splaydown_assemble_and_fix_header(const node_ptr & t, const node_ptr & header, const node_ptr &leftmost, const node_ptr &rightmost)
: t_(t)
, null_node_(header)
, l_(null_node_)
, r_(null_node_)
, leftmost_(leftmost)
, rightmost_(rightmost)
{}
~splaydown_assemble_and_fix_header()
{
this->assemble();
//Now recover the original header except for the
//splayed root node.
//"t_" is the current root and "null_node_" is the header node
NodeTraits::set_parent(null_node_, t_);
NodeTraits::set_parent(t_, null_node_);
//Recover leftmost/rightmost pointers
NodeTraits::set_left (null_node_, leftmost_);
NodeTraits::set_right(null_node_, rightmost_);
}
private:
void assemble()
{
//procedure assemble;
// left(r), right(l) := right(t), left(t);
// left(t), right(t) := right(null), left(null);
//end assemble;
{ // left(r), right(l) := right(t), left(t);
node_ptr const old_t_left = NodeTraits::get_left(t_);
node_ptr const old_t_right = NodeTraits::get_right(t_);
NodeTraits::set_right(l_, old_t_left);
NodeTraits::set_left (r_, old_t_right);
if(old_t_left){
NodeTraits::set_parent(old_t_left, l_);
}
if(old_t_right){
NodeTraits::set_parent(old_t_right, r_);
}
}
{ // left(t), right(t) := right(null), left(null);
node_ptr const null_right = NodeTraits::get_right(null_node_);
node_ptr const null_left = NodeTraits::get_left(null_node_);
NodeTraits::set_left (t_, null_right);
NodeTraits::set_right(t_, null_left);
if(null_right){
NodeTraits::set_parent(null_right, t_);
}
if(null_left){
NodeTraits::set_parent(null_left, t_);
}
}
}
public:
node_ptr t_, null_node_, l_, r_, 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 to speed up range deletions.
static void erase(const node_ptr & header, const node_ptr & z)
{
//posibility 1
if(NodeTraits::get_left(z)){
splay_up(bstree_algo::prev_node(z), header);
}
//possibility 2
//if(NodeTraits::get_left(z)){
// node_ptr l = NodeTraits::get_left(z);
// splay_up(l, header);
//}
//if(NodeTraits::get_left(z)){
// node_ptr l = bstree_algo::prev_node(z);
// splay_up_impl(l, z);
//}
//possibility 4
//splay_up(z, header);
bstree_algo::erase(header, z);
}
//! @copydoc ::boost::intrusive::bstree_algorithms::transfer_unique
template<class NodePtrCompare>
static bool transfer_unique
(const node_ptr & header1, NodePtrCompare comp, const node_ptr &header2, const node_ptr & z)
{
typename bstree_algo::insert_commit_data commit_data;
bool const transferable = bstree_algo::insert_unique_check(header1, z, comp, commit_data).second;
if(transferable){
erase(header2, z);
bstree_algo::insert_commit(header1, z, commit_data);
splay_up(z, header1);
}
return transferable;
}
//! @copydoc ::boost::intrusive::bstree_algorithms::transfer_equal
template<class NodePtrCompare>
static void transfer_equal
(const node_ptr & header1, NodePtrCompare comp, const node_ptr &header2, const node_ptr & z)
{
insert_commit_data commit_data;
splay_down(header1, z, comp);
bstree_algo::insert_equal_upper_bound_check(header1, z, comp, commit_data);
erase(header2, z);
bstree_algo::insert_commit(header1, z, commit_data);
}
#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: an element with key `key` 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.
template<class KeyType, class KeyNodePtrCompare>
static node_ptr lower_bound
(const node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
{
splay_down(detail::uncast(header), key, comp);
node_ptr y = bstree_algo::lower_bound(header, key, comp);
//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.
template<class KeyType, class KeyNodePtrCompare>
static node_ptr upper_bound
(const node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
{
splay_down(detail::uncast(header), key, comp);
node_ptr y = bstree_algo::upper_bound(header, key, comp);
//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.
template<class KeyType, class KeyNodePtrCompare>
static node_ptr find
(const node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
{
splay_down(detail::uncast(header), key, comp);
return bstree_algo::find(header, key, comp);
}
//! @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.
template<class KeyType, class KeyNodePtrCompare>
static std::pair<node_ptr, node_ptr> equal_range
(const node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
{
splay_down(detail::uncast(header), key, comp);
std::pair<node_ptr, node_ptr> ret = bstree_algo::equal_range(header, key, comp);
//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::lower_bound_range(const const_node_ptr&,const KeyType&,KeyNodePtrCompare)
//! Additional notes: the first node of the range is splayed.
template<class KeyType, class KeyNodePtrCompare>
static std::pair<node_ptr, node_ptr> lower_bound_range
(const node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
{
splay_down(detail::uncast(header), key, comp);
std::pair<node_ptr, node_ptr> ret = bstree_algo::lower_bound_range(header, key, comp);
//splay_up(ret.first, detail::uncast(header));
return ret;
}
//! @copydoc ::boost::intrusive::bstree_algorithms::lower_bound_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> lower_bound_range
(const const_node_ptr & header, const KeyType &key, KeyNodePtrCompare comp)
{ return bstree_algo::lower_bound_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.
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)
{
splay_down(detail::uncast(header), lower_key, comp);
std::pair<node_ptr, node_ptr> ret =
bstree_algo::bounded_range(header, lower_key, upper_key, comp, left_closed, right_closed);
//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)
{ priv_splay_up<true>(node, header); }
// 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, bool *pfound = 0)
{ return priv_splay_down<true>(header, key, comp, pfound); }
private:
/// @cond
// bottom-up splay, use data_ as parent for n | complexity : logarithmic | exception : nothrow
template<bool SimpleSplay>
static void priv_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);
if(!SimpleSplay){
rotate(n);
}
}
}
}
template<bool SimpleSplay, class KeyType, class KeyNodePtrCompare>
static node_ptr priv_splay_down(const node_ptr & header, const KeyType &key, KeyNodePtrCompare comp, bool *pfound = 0)
{
//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 const old_root = NodeTraits::get_parent(header);
node_ptr const leftmost = NodeTraits::get_left(header);
node_ptr const rightmost = NodeTraits::get_right(header);
if(leftmost == rightmost){ //Empty or unique node
if(pfound){
*pfound = old_root && !comp(key, old_root) && !comp(old_root, key);
}
return old_root ? old_root : header;
}
else{
//Initialize "null node" (the header in our case)
NodeTraits::set_left (header, node_ptr());
NodeTraits::set_right(header, node_ptr());
//Class that will backup leftmost/rightmost from header, commit the assemble(),
//and will restore leftmost/rightmost to header even if "comp" throws
detail::splaydown_assemble_and_fix_header<NodeTraits> commit(old_root, header, leftmost, rightmost);
bool found = false;
for( ;; ){
if(comp(key, commit.t_)){
node_ptr const t_left = NodeTraits::get_left(commit.t_);
if(!t_left)
break;
if(comp(key, t_left)){
bstree_algo::rotate_right_no_parent_fix(commit.t_, t_left);
commit.t_ = t_left;
if( !NodeTraits::get_left(commit.t_) )
break;
link_right(commit.t_, commit.r_);
}
else{
link_right(commit.t_, commit.r_);
if(!SimpleSplay && comp(t_left, key)){
if( !NodeTraits::get_right(commit.t_) )
break;
link_left(commit.t_, commit.l_);
}
}
}
else if(comp(commit.t_, key)){
node_ptr const t_right = NodeTraits::get_right(commit.t_);
if(!t_right)
break;
if(comp(t_right, key)){
bstree_algo::rotate_left_no_parent_fix(commit.t_, t_right);
commit.t_ = t_right;
if( !NodeTraits::get_right(commit.t_) )
break;
link_left(commit.t_, commit.l_);
}
else{
link_left(commit.t_, commit.l_);
if(!SimpleSplay && comp(key, t_right)){
if( !NodeTraits::get_left(commit.t_) )
break;
link_right(commit.t_, commit.r_);
}
}
}
else{
found = true;
break;
}
}
//commit.~splaydown_assemble_and_fix_header<NodeTraits>() will first
//"assemble()" + link the new root & recover header's leftmost & rightmost
if(pfound){
*pfound = found;
}
return commit.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)
{
//procedure link_left;
// t, l, right(l) := right(t), t, t
//end link_left
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)
{
//procedure link_right;
// t, r, left(r) := left(t), t, t
//end link_right;
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)
{
//procedure rotate_left;
// t, right(t), left(right(t)) := right(t), left(right(t)), t
//end rotate_left;
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))
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))
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;
};
template <class ValueTraits, class NodePtrCompare, class ExtraChecker>
struct get_node_checker<SplayTreeAlgorithms, ValueTraits, NodePtrCompare, ExtraChecker>
{
typedef detail::bstree_node_checker<ValueTraits, NodePtrCompare, ExtraChecker> type;
};
/// @endcond
} //namespace intrusive
} //namespace boost
#include <boost/intrusive/detail/config_end.hpp>
#endif //BOOST_INTRUSIVE_SPLAYTREE_ALGORITHMS_HPP
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