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glm/test/external/boost/intrusive/detail/tree_algorithms.hpp

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/////////////////////////////////////////////////////////////////////////////
//
// (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