kicad/include/boost/heap/binomial_heap.hpp

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29 KiB
C++

// boost heap: binomial heap
//
// Copyright (C) 2010 Tim Blechmann
//
// 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)
#ifndef BOOST_HEAP_BINOMIAL_HEAP_HPP
#define BOOST_HEAP_BINOMIAL_HEAP_HPP
#include <algorithm>
#include <vector>
#include <boost/assert.hpp>
#include <boost/heap/detail/heap_comparison.hpp>
#include <boost/heap/detail/heap_node.hpp>
#include <boost/heap/detail/stable_heap.hpp>
#include <boost/heap/detail/tree_iterator.hpp>
#ifndef BOOST_DOXYGEN_INVOKED
#ifdef BOOST_HEAP_SANITYCHECKS
#define BOOST_HEAP_ASSERT BOOST_ASSERT
#else
#define BOOST_HEAP_ASSERT(expression)
#endif
#endif
namespace boost {
namespace heap {
namespace detail {
typedef parameter::parameters<boost::parameter::optional<tag::allocator>,
boost::parameter::optional<tag::compare>,
boost::parameter::optional<tag::stable>,
boost::parameter::optional<tag::constant_time_size>,
boost::parameter::optional<tag::stability_counter_type>
> binomial_heap_signature;
template <typename T, typename Parspec>
struct make_binomial_heap_base
{
static const bool constant_time_size = parameter::binding<Parspec,
tag::constant_time_size,
boost::mpl::true_
>::type::value;
typedef typename detail::make_heap_base<T, Parspec, constant_time_size>::type base_type;
typedef typename detail::make_heap_base<T, Parspec, constant_time_size>::allocator_argument allocator_argument;
typedef typename detail::make_heap_base<T, Parspec, constant_time_size>::compare_argument compare_argument;
typedef parent_pointing_heap_node<typename base_type::internal_type> node_type;
typedef typename allocator_argument::template rebind<node_type>::other allocator_type;
struct type:
base_type,
allocator_type
{
type(compare_argument const & arg):
base_type(arg)
{}
#ifdef BOOST_HAS_RVALUE_REFS
type(type && rhs):
base_type(std::move(static_cast<base_type&>(rhs))),
allocator_type(std::move(static_cast<allocator_type&>(rhs)))
{}
type & operator=(type && rhs)
{
base_type::operator=(std::move(static_cast<base_type&>(rhs)));
allocator_type::operator=(std::move(static_cast<allocator_type&>(rhs)));
return *this;
}
type & operator=(type const & rhs)
{
base_type::operator=(static_cast<base_type const &>(rhs));
allocator_type::operator=(static_cast<allocator_type const &>(rhs));
return *this;
}
#endif
};
};
}
/**
* \class binomial_heap
* \brief binomial heap
*
* The template parameter T is the type to be managed by the container.
* The user can specify additional options and if no options are provided default options are used.
*
* The container supports the following options:
* - \c boost::heap::stable<>, defaults to \c stable<false>
* - \c boost::heap::compare<>, defaults to \c compare<std::less<T> >
* - \c boost::heap::allocator<>, defaults to \c allocator<std::allocator<T> >
* - \c boost::heap::constant_time_size<>, defaults to \c constant_time_size<true>
* - \c boost::heap::stability_counter_type<>, defaults to \c stability_counter_type<boost::uintmax_t>
*
*/
#ifdef BOOST_DOXYGEN_INVOKED
template<class T, class ...Options>
#else
template <typename T,
class A0 = boost::parameter::void_,
class A1 = boost::parameter::void_,
class A2 = boost::parameter::void_,
class A3 = boost::parameter::void_
>
#endif
class binomial_heap:
private detail::make_binomial_heap_base<T,
typename detail::binomial_heap_signature::bind<A0, A1, A2, A3>::type
>::type
{
typedef typename detail::binomial_heap_signature::bind<A0, A1, A2, A3>::type bound_args;
typedef detail::make_binomial_heap_base<T, bound_args> base_maker;
typedef typename base_maker::type super_t;
typedef typename super_t::internal_type internal_type;
typedef typename super_t::size_holder_type size_holder;
typedef typename base_maker::allocator_argument allocator_argument;
template <typename Heap1, typename Heap2>
friend struct heap_merge_emulate;
public:
static const bool constant_time_size = super_t::constant_time_size;
static const bool has_ordered_iterators = true;
static const bool is_mergable = true;
static const bool is_stable = detail::extract_stable<bound_args>::value;
static const bool has_reserve = false;
private:
#ifndef BOOST_DOXYGEN_INVOKED
struct implementation_defined:
detail::extract_allocator_types<typename base_maker::allocator_argument>
{
typedef T value_type;
typedef typename detail::extract_allocator_types<typename base_maker::allocator_argument>::size_type size_type;
typedef typename detail::extract_allocator_types<typename base_maker::allocator_argument>::reference reference;
typedef typename base_maker::compare_argument value_compare;
typedef typename base_maker::allocator_type allocator_type;
typedef typename allocator_type::pointer node_pointer;
typedef typename allocator_type::const_pointer const_node_pointer;
typedef detail::node_handle<node_pointer, super_t, reference> handle_type;
typedef typename base_maker::node_type node_type;
typedef boost::intrusive::list<detail::heap_node_base<false>,
boost::intrusive::constant_time_size<true>
> node_list_type;
typedef typename node_list_type::iterator node_list_iterator;
typedef typename node_list_type::const_iterator node_list_const_iterator;
typedef detail::value_extractor<value_type, internal_type, super_t> value_extractor;
typedef detail::recursive_tree_iterator<node_type,
node_list_const_iterator,
const value_type,
value_extractor,
detail::list_iterator_converter<node_type, node_list_type>
> iterator;
typedef iterator const_iterator;
typedef detail::tree_iterator<node_type,
const value_type,
allocator_type,
value_extractor,
detail::list_iterator_converter<node_type, node_list_type>,
true,
true,
value_compare
> ordered_iterator;
};
#endif
public:
typedef T value_type;
typedef typename implementation_defined::size_type size_type;
typedef typename implementation_defined::difference_type difference_type;
typedef typename implementation_defined::value_compare value_compare;
typedef typename implementation_defined::allocator_type allocator_type;
typedef typename implementation_defined::reference reference;
typedef typename implementation_defined::const_reference const_reference;
typedef typename implementation_defined::pointer pointer;
typedef typename implementation_defined::const_pointer const_pointer;
/// \copydoc boost::heap::priority_queue::iterator
typedef typename implementation_defined::iterator iterator;
typedef typename implementation_defined::const_iterator const_iterator;
typedef typename implementation_defined::ordered_iterator ordered_iterator;
typedef typename implementation_defined::handle_type handle_type;
private:
typedef typename implementation_defined::node_type node_type;
typedef typename implementation_defined::node_list_type node_list_type;
typedef typename implementation_defined::node_pointer node_pointer;
typedef typename implementation_defined::const_node_pointer const_node_pointer;
typedef typename implementation_defined::node_list_iterator node_list_iterator;
typedef typename implementation_defined::node_list_const_iterator node_list_const_iterator;
typedef typename super_t::internal_compare internal_compare;
public:
/// \copydoc boost::heap::priority_queue::priority_queue(value_compare const &)
explicit binomial_heap(value_compare const & cmp = value_compare()):
super_t(cmp), top_element(0)
{}
/// \copydoc boost::heap::priority_queue::priority_queue(priority_queue const &)
binomial_heap(binomial_heap const & rhs):
super_t(rhs), top_element(0)
{
if (rhs.empty())
return;
clone_forest(rhs);
size_holder::set_size(rhs.get_size());
}
/// \copydoc boost::heap::priority_queue::operator=(priority_queue const &)
binomial_heap & operator=(binomial_heap const & rhs)
{
clear();
size_holder::set_size(rhs.get_size());
static_cast<super_t&>(*this) = rhs;
if (rhs.empty())
top_element = NULL;
else
clone_forest(rhs);
return *this;
}
#ifdef BOOST_HAS_RVALUE_REFS
/// \copydoc boost::heap::priority_queue::priority_queue(priority_queue &&)
binomial_heap(binomial_heap && rhs):
super_t(std::move(rhs)), top_element(rhs.top_element)
{
trees.splice(trees.begin(), rhs.trees);
rhs.top_element = NULL;
}
/// \copydoc boost::heap::priority_queue::operator=(priority_queue &&)
binomial_heap & operator=(binomial_heap && rhs)
{
clear();
super_t::operator=(std::move(rhs));
trees.splice(trees.begin(), rhs.trees);
top_element = rhs.top_element;
rhs.top_element = NULL;
return *this;
}
#endif
~binomial_heap(void)
{
clear();
}
/// \copydoc boost::heap::priority_queue::empty
bool empty(void) const
{
return top_element == NULL;
}
/**
* \b Effects: Returns the number of elements contained in the priority queue.
*
* \b Complexity: Constant, if configured with constant_time_size<true>, otherwise linear.
*
* */
size_type size(void) const
{
if (constant_time_size)
return size_holder::get_size();
if (empty())
return 0;
else
return detail::count_list_nodes<node_type, node_list_type>(trees);
}
/// \copydoc boost::heap::priority_queue::max_size
size_type max_size(void) const
{
return allocator_type::max_size();
}
/// \copydoc boost::heap::priority_queue::clear
void clear(void)
{
typedef detail::node_disposer<node_type, typename node_list_type::value_type, allocator_type> disposer;
trees.clear_and_dispose(disposer(*this));
size_holder::set_size(0);
top_element = NULL;
}
/// \copydoc boost::heap::priority_queue::get_allocator
allocator_type get_allocator(void) const
{
return *this;
}
/// \copydoc boost::heap::priority_queue::swap
void swap(binomial_heap & rhs)
{
super_t::swap(rhs);
std::swap(top_element, rhs.top_element);
trees.swap(rhs.trees);
}
/// \copydoc boost::heap::priority_queue::top
const_reference top(void) const
{
BOOST_ASSERT(!empty());
return super_t::get_value(top_element->value);
}
/**
* \b Effects: Adds a new element to the priority queue. Returns handle to element
*
* \b Complexity: Logarithmic.
*
* */
handle_type push(value_type const & v)
{
node_pointer n = allocator_type::allocate(1);
new(n) node_type(super_t::make_node(v));
insert_node(trees.begin(), n);
if (!top_element || super_t::operator()(top_element->value, n->value))
top_element = n;
size_holder::increment();
sanity_check();
return handle_type(n);
}
#if defined(BOOST_HAS_RVALUE_REFS) && !defined(BOOST_NO_VARIADIC_TEMPLATES)
/**
* \b Effects: Adds a new element to the priority queue. The element is directly constructed in-place. Returns handle to element.
*
* \b Complexity: Logarithmic.
*
* */
template <class... Args>
handle_type emplace(Args&&... args)
{
node_pointer n = allocator_type::allocate(1);
new(n) node_type(super_t::make_node(std::forward<Args>(args)...));
insert_node(trees.begin(), n);
if (!top_element || super_t::operator()(top_element->value, n->value))
top_element = n;
size_holder::increment();
sanity_check();
return handle_type(n);
}
#endif
/**
* \b Effects: Removes the top element from the priority queue.
*
* \b Complexity: Logarithmic.
*
* */
void pop(void)
{
BOOST_ASSERT(!empty());
node_pointer element = top_element;
trees.erase(node_list_type::s_iterator_to(*element));
size_holder::decrement();
if (element->child_count()) {
size_type sz = (1 << element->child_count()) - 1;
binomial_heap children(value_comp(), element->children, sz);
if (trees.empty())
swap(children);
else
merge_and_clear_nodes(children);
}
if (trees.empty())
top_element = NULL;
else
update_top_element();
element->~node_type();
allocator_type::deallocate(element, 1);
sanity_check();
}
/**
* \b Effects: Assigns \c v to the element handled by \c handle & updates the priority queue.
*
* \b Complexity: Logarithmic.
*
* */
void update (handle_type handle, const_reference v)
{
if (super_t::operator()(super_t::get_value(handle.node_->value), v))
increase(handle, v);
else
decrease(handle, v);
}
/**
* \b Effects: Updates the heap after the element handled by \c handle has been changed.
*
* \b Complexity: Logarithmic.
*
* \b Note: If this is not called, after a handle has been updated, the behavior of the data structure is undefined!
* */
void update (handle_type handle)
{
node_pointer this_node = handle.node_;
if (this_node->parent) {
if (super_t::operator()(super_t::get_value(this_node->parent->value), super_t::get_value(this_node->value)))
increase(handle);
else
decrease(handle);
}
else
decrease(handle);
}
/**
* \b Effects: Assigns \c v to the element handled by \c handle & updates the priority queue.
*
* \b Complexity: Logarithmic.
*
* \b Note: The new value is expected to be greater than the current one
* */
void increase (handle_type handle, const_reference v)
{
handle.node_->value = super_t::make_node(v);
increase(handle);
}
/**
* \b Effects: Updates the heap after the element handled by \c handle has been changed.
*
* \b Complexity: Logarithmic.
*
* \b Note: If this is not called, after a handle has been updated, the behavior of the data structure is undefined!
* */
void increase (handle_type handle)
{
node_pointer n = handle.node_;
siftup(n, *this);
update_top_element();
sanity_check();
}
/**
* \b Effects: Assigns \c v to the element handled by \c handle & updates the priority queue.
*
* \b Complexity: Logarithmic.
*
* \b Note: The new value is expected to be less than the current one
* */
void decrease (handle_type handle, const_reference v)
{
handle.node_->value = super_t::make_node(v);
decrease(handle);
}
/**
* \b Effects: Updates the heap after the element handled by \c handle has been changed.
*
* \b Complexity: Logarithmic.
*
* \b Note: The new value is expected to be less than the current one. If this is not called, after a handle has been updated, the behavior of the data structure is undefined!
* */
void decrease (handle_type handle)
{
node_pointer n = handle.node_;
siftdown(n);
if (n == top_element)
update_top_element();
}
/**
* \b Effects: Merge with priority queue rhs.
*
* \b Complexity: Logarithmic.
*
* */
void merge(binomial_heap & rhs)
{
if (rhs.empty())
return;
if (empty()) {
swap(rhs);
return;
}
size_type new_size = size_holder::get_size() + rhs.get_size();
merge_and_clear_nodes(rhs);
size_holder::set_size(new_size);
rhs.set_size(0);
rhs.top_element = NULL;
super_t::set_stability_count(std::max(super_t::get_stability_count(),
rhs.get_stability_count()));
rhs.set_stability_count(0);
}
public:
/// \copydoc boost::heap::priority_queue::begin
iterator begin(void) const
{
return iterator(trees.begin());
}
/// \copydoc boost::heap::priority_queue::end
iterator end(void) const
{
return iterator(trees.end());
}
/// \copydoc boost::heap::fibonacci_heap::ordered_begin
ordered_iterator ordered_begin(void) const
{
return ordered_iterator(trees.begin(), trees.end(), top_element, super_t::value_comp());
}
/// \copydoc boost::heap::fibonacci_heap::ordered_end
ordered_iterator ordered_end(void) const
{
return ordered_iterator(NULL, super_t::value_comp());
}
/**
* \b Effects: Removes the element handled by \c handle from the priority_queue.
*
* \b Complexity: Logarithmic.
* */
void erase(handle_type handle)
{
node_pointer n = handle.node_;
siftup(n, force_inf());
top_element = n;
pop();
}
/// \copydoc boost::heap::d_ary_heap_mutable::s_handle_from_iterator
static handle_type s_handle_from_iterator(iterator const & it)
{
return handle_type(&*it);
}
/// \copydoc boost::heap::priority_queue::value_comp
value_compare const & value_comp(void) const
{
return super_t::value_comp();
}
/// \copydoc boost::heap::priority_queue::operator<(HeapType const & rhs) const
template <typename HeapType>
bool operator<(HeapType const & rhs) const
{
return detail::heap_compare(*this, rhs);
}
/// \copydoc boost::heap::priority_queue::operator>(HeapType const & rhs) const
template <typename HeapType>
bool operator>(HeapType const & rhs) const
{
return detail::heap_compare(rhs, *this);
}
/// \copydoc boost::heap::priority_queue::operator>=(HeapType const & rhs) const
template <typename HeapType>
bool operator>=(HeapType const & rhs) const
{
return !operator<(rhs);
}
/// \copydoc boost::heap::priority_queue::operator<=(HeapType const & rhs) const
template <typename HeapType>
bool operator<=(HeapType const & rhs) const
{
return !operator>(rhs);
}
/// \copydoc boost::heap::priority_queue::operator==(HeapType const & rhs) const
template <typename HeapType>
bool operator==(HeapType const & rhs) const
{
return detail::heap_equality(*this, rhs);
}
/// \copydoc boost::heap::priority_queue::operator!=(HeapType const & rhs) const
template <typename HeapType>
bool operator!=(HeapType const & rhs) const
{
return !(*this == rhs);
}
private:
#if !defined(BOOST_DOXYGEN_INVOKED)
void merge_and_clear_nodes(binomial_heap & rhs)
{
BOOST_HEAP_ASSERT (!empty());
BOOST_HEAP_ASSERT (!rhs.empty());
node_list_iterator this_iterator = trees.begin();
node_pointer carry_node = NULL;
while (!rhs.trees.empty()) {
node_pointer rhs_node = static_cast<node_pointer>(&rhs.trees.front());
size_type rhs_degree = rhs_node->child_count();
if (super_t::operator()(top_element->value, rhs_node->value))
top_element = rhs_node;
try_again:
node_pointer this_node = static_cast<node_pointer>(&*this_iterator);
size_type this_degree = this_node->child_count();
sorted_by_degree();
rhs.sorted_by_degree();
if (this_degree == rhs_degree) {
if (carry_node) {
if (carry_node->child_count() < this_degree) {
trees.insert(this_iterator, *carry_node);
carry_node = NULL;
} else {
rhs.trees.pop_front();
carry_node = merge_trees(carry_node, rhs_node);
}
++this_iterator;
} else {
this_iterator = trees.erase(this_iterator);
rhs.trees.pop_front();
carry_node = merge_trees(this_node, rhs_node);
}
if (this_iterator == trees.end())
break;
else
continue;
}
if (this_degree < rhs_degree) {
if (carry_node) {
if (carry_node->child_count() < this_degree) {
trees.insert(this_iterator, *carry_node);
carry_node = NULL;
++this_iterator;
} else if (carry_node->child_count() == rhs_degree) {
rhs.trees.pop_front();
carry_node = merge_trees(carry_node, rhs_node);
continue;
} else {
this_iterator = trees.erase(this_iterator);
carry_node = merge_trees(this_node, carry_node);
}
goto try_again;
} else {
++this_iterator;
if (this_iterator == trees.end())
break;
goto try_again;
}
if (this_iterator == trees.end())
break;
else
continue;
}
if (this_degree > rhs_degree) {
rhs.trees.pop_front();
if (carry_node) {
if (carry_node->child_count() < rhs_degree) {
trees.insert(this_iterator, *carry_node);
trees.insert(this_iterator, *rhs_node);
carry_node = NULL;
} else
carry_node = merge_trees(rhs_node, carry_node);
} else
trees.insert(this_iterator, *rhs_node);
}
}
if (!rhs.trees.empty()) {
if (carry_node) {
node_list_iterator rhs_it = rhs.trees.begin();
while (static_cast<node_pointer>(&*rhs_it)->child_count() < carry_node->child_count())
++rhs_it;
rhs.insert_node(rhs_it, carry_node);
rhs.increment();
sorted_by_degree();
rhs.sorted_by_degree();
if (trees.empty()) {
trees.splice(trees.end(), rhs.trees, rhs.trees.begin(), rhs.trees.end());
update_top_element();
} else
merge_and_clear_nodes(rhs);
} else
trees.splice(trees.end(), rhs.trees, rhs.trees.begin(), rhs.trees.end());
return;
}
if (carry_node)
insert_node(this_iterator, carry_node);
}
void clone_forest(binomial_heap const & rhs)
{
BOOST_HEAP_ASSERT(trees.empty());
typedef typename node_type::template node_cloner<allocator_type> node_cloner;
trees.clone_from(rhs.trees, node_cloner(*this, NULL), detail::nop_disposer());
update_top_element();
}
struct force_inf
{
template <typename X>
bool operator()(X const &, X const &) const
{
return false;
}
};
template <typename Compare>
void siftup(node_pointer n, Compare const & cmp)
{
while (n->parent) {
node_pointer parent = n->parent;
node_pointer grand_parent = parent->parent;
if (cmp(n->value, parent->value))
return;
n->remove_from_parent();
n->swap_children(parent);
n->update_children();
parent->update_children();
if (grand_parent) {
parent->remove_from_parent();
grand_parent->add_child(n);
} else {
node_list_iterator it = trees.erase(node_list_type::s_iterator_to(*parent));
trees.insert(it, *n);
}
n->add_child(parent);
BOOST_HEAP_ASSERT(parent->child_count() == n->child_count());
}
}
void siftdown(node_pointer n)
{
while (n->child_count()) {
node_pointer max_child = detail::find_max_child<node_list_type, node_type, internal_compare>(n->children, super_t::get_internal_cmp());
if (super_t::operator()(max_child->value, n->value))
return;
max_child->remove_from_parent();
n->swap_children(max_child);
n->update_children();
max_child->update_children();
node_pointer parent = n->parent;
if (parent) {
n->remove_from_parent();
max_child->add_child(n);
parent->add_child(max_child);
} else {
node_list_iterator position = trees.erase(node_list_type::s_iterator_to(*n));
max_child->add_child(n);
trees.insert(position, *max_child);
}
}
}
void insert_node(node_list_iterator it, node_pointer n)
{
if (it != trees.end())
BOOST_HEAP_ASSERT(static_cast<node_pointer>(&*it)->child_count() >= n->child_count());
while(true) {
BOOST_HEAP_ASSERT(!n->is_linked());
if (it == trees.end())
break;
node_pointer this_node = static_cast<node_pointer>(&*it);
size_type this_degree = this_node->child_count();
size_type n_degree = n->child_count();
if (this_degree == n_degree) {
BOOST_HEAP_ASSERT(it->is_linked());
it = trees.erase(it);
n = merge_trees(n, this_node);
} else
break;
}
trees.insert(it, *n);
}
// private constructor, just used in pop()
explicit binomial_heap(value_compare const & cmp, node_list_type & child_list, size_type size):
super_t(cmp)
{
size_holder::set_size(size);
if (size)
top_element = static_cast<node_pointer>(&*child_list.begin()); // not correct, but we will reset it later
else
top_element = NULL;
for (node_list_iterator it = child_list.begin(); it != child_list.end(); ++it) {
node_pointer n = static_cast<node_pointer>(&*it);
n->parent = NULL;
}
trees.splice(trees.end(), child_list, child_list.begin(), child_list.end());
trees.sort(detail::cmp_by_degree<node_type>());
}
node_pointer merge_trees (node_pointer node1, node_pointer node2)
{
BOOST_HEAP_ASSERT(node1->child_count() == node2->child_count());
if (super_t::operator()(node1->value, node2->value))
std::swap(node1, node2);
if (node2->parent)
node2->remove_from_parent();
node1->add_child(node2);
return node1;
}
void update_top_element(void)
{
top_element = detail::find_max_child<node_list_type, node_type, internal_compare>(trees, super_t::get_internal_cmp());
}
void sorted_by_degree(void) const
{
#ifdef BOOST_HEAP_SANITYCHECKS
int degree = -1;
for (node_list_const_iterator it = trees.begin(); it != trees.end(); ++it) {
const_node_pointer n = static_cast<const_node_pointer>(&*it);
BOOST_HEAP_ASSERT(int(n->child_count()) > degree);
degree = n->child_count();
BOOST_HEAP_ASSERT((detail::is_heap<node_type, super_t>(n, *this)));
size_type child_nodes = detail::count_nodes<node_type>(n);
BOOST_HEAP_ASSERT(child_nodes == size_type(1 << static_cast<const_node_pointer>(&*it)->child_count()));
}
#endif
}
void sanity_check(void)
{
#ifdef BOOST_HEAP_SANITYCHECKS
sorted_by_degree();
if (!empty()) {
node_pointer found_top = detail::find_max_child<node_list_type, node_type, internal_compare>(trees, super_t::get_internal_cmp());
BOOST_HEAP_ASSERT(top_element == found_top);
}
if (constant_time_size) {
size_t counted = detail::count_list_nodes<node_type, node_list_type>(trees);
size_t stored = size_holder::get_size();
BOOST_HEAP_ASSERT(counted == stored);
}
#endif
}
node_pointer top_element;
node_list_type trees;
#endif // BOOST_DOXYGEN_INVOKED
};
} /* namespace heap */
} /* namespace boost */
#undef BOOST_HEAP_ASSERT
#endif /* BOOST_HEAP_D_ARY_HEAP_HPP */