kicad/include/boost/heap/skew_heap.hpp

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2012-05-16 01:42:04 +00:00
// boost heap: skew 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_SKEW_HEAP_HPP
#define BOOST_HEAP_SKEW_HEAP_HPP
#include <algorithm>
#include <utility>
#include <vector>
#include <boost/assert.hpp>
#include <boost/array.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 {
template <typename node_pointer, bool store_parent_pointer>
struct parent_holder
{
parent_holder(void):
parent_(NULL)
{}
void set_parent(node_pointer parent)
{
BOOST_HEAP_ASSERT(static_cast<node_pointer>(this) != parent);
parent_ = parent;
}
node_pointer get_parent(void) const
{
return parent_;
}
node_pointer parent_;
};
template <typename node_pointer>
struct parent_holder<node_pointer, false>
{
void set_parent(node_pointer parent)
{}
node_pointer get_parent(void) const
{
return NULL;
}
};
template <typename value_type, bool store_parent_pointer>
struct skew_heap_node:
parent_holder<skew_heap_node<value_type, store_parent_pointer>*, store_parent_pointer>
{
typedef parent_holder<skew_heap_node<value_type, store_parent_pointer>*, store_parent_pointer> super_t;
typedef boost::array<skew_heap_node*, 2> child_list_type;
typedef typename child_list_type::iterator child_iterator;
typedef typename child_list_type::const_iterator const_child_iterator;
skew_heap_node(value_type const & v):
value(v)
{
children.assign(0);
}
#ifdef BOOST_HAS_RVALUE_REFS
skew_heap_node(value_type && v):
value(v)
{
children.assign(0);
}
#endif
template <typename Alloc>
skew_heap_node (skew_heap_node const & rhs, Alloc & allocator, skew_heap_node * parent):
value(rhs.value)
{
super_t::set_parent(parent);
node_cloner<skew_heap_node, skew_heap_node, Alloc> cloner(allocator);
clone_child(0, rhs, cloner);
clone_child(1, rhs, cloner);
}
template <typename Cloner>
void clone_child(int index, skew_heap_node const & rhs, Cloner & cloner)
{
if (rhs.children[index])
children[index] = cloner(*rhs.children[index], this);
else
children[index] = NULL;
}
template <typename Alloc>
void clear_subtree(Alloc & alloc)
{
node_disposer<skew_heap_node, skew_heap_node, Alloc> disposer(alloc);
dispose_child(children[0], disposer);
dispose_child(children[1], disposer);
}
template <typename Disposer>
void dispose_child(skew_heap_node * node, Disposer & disposer)
{
if (node)
disposer(node);
}
std::size_t count_children(void) const
{
size_t ret = 1;
if (children[0])
ret += children[0]->count_children();
if (children[1])
ret += children[1]->count_children();
return ret;
}
template <typename HeapBase>
bool is_heap(typename HeapBase::value_compare const & cmp) const
{
for (const_child_iterator it = children.begin(); it != children.end(); ++it) {
const skew_heap_node * child = *it;
if (child == NULL)
continue;
if (store_parent_pointer)
BOOST_HEAP_ASSERT(child->get_parent() == this);
if (cmp(HeapBase::get_value(value), HeapBase::get_value(child->value)) ||
!child->is_heap<HeapBase>(cmp))
return false;
}
return true;
}
value_type value;
boost::array<skew_heap_node*, 2> children;
};
typedef parameter::parameters<boost::parameter::optional<tag::allocator>,
boost::parameter::optional<tag::compare>,
boost::parameter::optional<tag::stable>,
boost::parameter::optional<tag::store_parent_pointer>,
boost::parameter::optional<tag::stability_counter_type>,
boost::parameter::optional<tag::constant_time_size>,
boost::parameter::optional<tag::mutable_>
> skew_heap_signature;
template <typename T, typename BoundArgs>
struct make_skew_heap_base
{
static const bool constant_time_size = parameter::binding<BoundArgs,
tag::constant_time_size,
boost::mpl::true_
>::type::value;
typedef typename make_heap_base<T, BoundArgs, constant_time_size>::type base_type;
typedef typename make_heap_base<T, BoundArgs, constant_time_size>::allocator_argument allocator_argument;
typedef typename make_heap_base<T, BoundArgs, constant_time_size>::compare_argument compare_argument;
static const bool is_mutable = extract_mutable<BoundArgs>::value;
static const bool store_parent_pointer = parameter::binding<BoundArgs,
tag::store_parent_pointer,
boost::mpl::false_>::type::value || is_mutable;
typedef skew_heap_node<typename base_type::internal_type, store_parent_pointer> 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
};
};
} /* namespace detail */
/**
* \class skew_heap
* \brief skew 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::compare<>, defaults to \c compare<std::less<T> >
* - \c boost::heap::stable<>, defaults to \c stable<false>
* - \c boost::heap::stability_counter_type<>, defaults to \c stability_counter_type<boost::uintmax_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::store_parent_pointer<>, defaults to \c store_parent_pointer<true>. Maintaining a parent pointer adds some
* maintenance and size overhead, but iterating a heap is more efficient.
* - \c boost::heap::mutable<>, defaults to \c mutable<false>.
*
*/
#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_,
class A4 = boost::parameter::void_,
class A5 = boost::parameter::void_,
class A6 = boost::parameter::void_
>
#endif
class skew_heap:
private detail::make_skew_heap_base<T,
typename detail::skew_heap_signature::bind<A0, A1, A2, A3, A4, A5, A6>::type
>::type
{
typedef typename detail::skew_heap_signature::bind<A0, A1, A2, A3, A4, A5, A6>::type bound_args;
typedef detail::make_skew_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;
static const bool store_parent_pointer = base_maker::store_parent_pointer;
template <typename Heap1, typename Heap2>
friend struct heap_merge_emulate;
struct implementation_defined:
detail::extract_allocator_types<typename base_maker::allocator_argument>
{
typedef T value_type;
typedef typename base_maker::compare_argument value_compare;
typedef typename base_maker::allocator_type allocator_type;
typedef typename base_maker::node_type node;
typedef typename allocator_type::pointer node_pointer;
typedef typename allocator_type::const_pointer const_node_pointer;
typedef detail::value_extractor<value_type, internal_type, super_t> value_extractor;
typedef boost::array<node_pointer, 2> child_list_type;
typedef typename child_list_type::iterator child_list_iterator;
typedef typename boost::mpl::if_c<false,
detail::recursive_tree_iterator<node,
child_list_iterator,
const value_type,
value_extractor,
detail::list_iterator_converter<node,
child_list_type
>
>,
detail::tree_iterator<node,
const value_type,
allocator_type,
value_extractor,
detail::dereferencer<node>,
true,
false,
value_compare
>
>::type iterator;
typedef iterator const_iterator;
typedef detail::tree_iterator<node,
const value_type,
allocator_type,
value_extractor,
detail::dereferencer<node>,
true,
true,
value_compare
> ordered_iterator;
typedef typename detail::extract_allocator_types<typename base_maker::allocator_argument>::reference reference;
typedef detail::node_handle<node_pointer, super_t, reference> handle_type;
};
typedef typename implementation_defined::value_extractor value_extractor;
typedef typename implementation_defined::node node;
typedef typename implementation_defined::node_pointer node_pointer;
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;
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;
static const bool is_mutable = detail::extract_mutable<bound_args>::value;
typedef typename mpl::if_c<is_mutable, typename implementation_defined::handle_type, void*>::type handle_type;
/// \copydoc boost::heap::priority_queue::priority_queue(value_compare const &)
explicit skew_heap(value_compare const & cmp = value_compare()):
super_t(cmp), root(NULL)
{}
/// \copydoc boost::heap::priority_queue::priority_queue(priority_queue const &)
skew_heap(skew_heap const & rhs):
super_t(rhs), root(0)
{
if (rhs.empty())
return;
clone_tree(rhs);
size_holder::set_size(rhs.get_size());
}
/// \copydoc boost::heap::priority_queue::operator=(priority_queue const & rhs)
skew_heap & operator=(skew_heap const & rhs)
{
clear();
size_holder::set_size(rhs.get_size());
static_cast<super_t&>(*this) = rhs;
clone_tree(rhs);
return *this;
}
#ifdef BOOST_HAS_RVALUE_REFS
/// \copydoc boost::heap::priority_queue::priority_queue(priority_queue &&)
skew_heap(skew_heap && rhs):
super_t(std::move(rhs)), root(rhs.root)
{
rhs.root = NULL;
}
/// \copydoc boost::heap::priority_queue::operator=(priority_queue &&)
skew_heap & operator=(skew_heap && rhs)
{
super_t::operator=(std::move(rhs));
root = rhs.root;
rhs.root = NULL;
return *this;
}
#endif
~skew_heap(void)
{
clear();
}
/**
* \b Effects: Adds a new element to the priority queue.
*
* \b Complexity: Logarithmic (amortized).
*
* */
typename mpl::if_c<is_mutable, handle_type, void>::type push(value_type const & v)
{
typedef typename mpl::if_c<is_mutable, push_handle, push_void>::type push_helper;
return push_helper::push(this, v);
}
#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.
*
* \b Complexity: Logarithmic (amortized).
*
* */
template <typename... Args>
typename mpl::if_c<is_mutable, handle_type, void>::type emplace(Args&&... args)
{
typedef typename mpl::if_c<is_mutable, push_handle, push_void>::type push_helper;
return push_helper::emplace(this, std::forward<Args>(args)...);
}
#endif
/// \copydoc boost::heap::priority_queue::empty
bool empty(void) const
{
return root == NULL;
}
/// \copydoc boost::heap::binomial_heap::size
size_type size(void) const
{
if (constant_time_size)
return size_holder::get_size();
if (root == NULL)
return 0;
else
return root->count_children();
}
/// \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)
{
if (empty())
return;
root->template clear_subtree<allocator_type>(*this);
root->~node();
allocator_type::deallocate(root, 1);
root = NULL;
size_holder::set_size(0);
}
/// \copydoc boost::heap::priority_queue::get_allocator
allocator_type get_allocator(void) const
{
return *this;
}
/// \copydoc boost::heap::priority_queue::swap
void swap(skew_heap & rhs)
{
super_t::swap(rhs);
std::swap(root, rhs.root);
}
/// \copydoc boost::heap::priority_queue::top
const_reference top(void) const
{
BOOST_ASSERT(!empty());
return super_t::get_value(root->value);
}
/**
* \b Effects: Removes the top element from the priority queue.
*
* \b Complexity: Logarithmic (amortized).
*
* */
void pop(void)
{
BOOST_ASSERT(!empty());
node_pointer top = root;
root = merge_children(root);
size_holder::decrement();
if (root)
BOOST_HEAP_ASSERT(root->get_parent() == NULL);
else
BOOST_HEAP_ASSERT(size_holder::get_size() == 0);
top->~node();
allocator_type::deallocate(top, 1);
sanity_check();
}
/// \copydoc boost::heap::priority_queue::begin
iterator begin(void) const
{
return iterator(root, super_t::value_comp());
}
/// \copydoc boost::heap::priority_queue::end
iterator end(void) const
{
return iterator();
}
/// \copydoc boost::heap::fibonacci_heap::ordered_begin
ordered_iterator ordered_begin(void) const
{
return ordered_iterator(root, super_t::value_comp());
}
/// \copydoc boost::heap::fibonacci_heap::ordered_begin
ordered_iterator ordered_end(void) const
{
return ordered_iterator(0, super_t::value_comp());
}
/**
* \b Effects: Merge all elements from rhs into this
*
* \b Complexity: Logarithmic (amortized).
*
* */
void merge(skew_heap & rhs)
{
if (rhs.empty())
return;
merge_node(rhs.root);
size_holder::add(rhs.get_size());
rhs.set_size(0);
rhs.root = NULL;
sanity_check();
super_t::set_stability_count(std::max(super_t::get_stability_count(),
rhs.get_stability_count()));
rhs.set_stability_count(0);
}
/// \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);
}
/// \copydoc boost::heap::d_ary_heap::s_handle_from_iterator
static handle_type s_handle_from_iterator(iterator const & it)
{
return handle_type(&*it);
}
/**
* \b Effects: Removes the element handled by \c handle from the priority_queue.
*
* \b Complexity: Logarithmic (amortized).
* */
void erase (handle_type object)
{
BOOST_STATIC_ASSERT(is_mutable);
node_pointer this_node = object.node_;
unlink_node(this_node);
size_holder::decrement();
sanity_check();
this_node->~node();
allocator_type::deallocate(this_node, 1);
}
/**
* \b Effects: Assigns \c v to the element handled by \c handle & updates the priority queue.
*
* \b Complexity: Logarithmic (amortized).
*
* */
void update (handle_type handle, const_reference v)
{
BOOST_STATIC_ASSERT(is_mutable);
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 (amortized).
*
* \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)
{
BOOST_STATIC_ASSERT(is_mutable);
node_pointer this_node = handle.node_;
if (this_node->get_parent()) {
if (super_t::operator()(super_t::get_value(this_node->get_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 (amortized).
*
* \b Note: The new value is expected to be greater than the current one
* */
void increase (handle_type handle, const_reference v)
{
BOOST_STATIC_ASSERT(is_mutable);
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 (amortized).
*
* \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)
{
BOOST_STATIC_ASSERT(is_mutable);
node_pointer this_node = handle.node_;
if (this_node == root)
return;
node_pointer parent = this_node->get_parent();
if (this_node == parent->children[0])
parent->children[0] = NULL;
else
parent->children[1] = NULL;
this_node->set_parent(NULL);
merge_node(this_node);
}
/**
* \b Effects: Assigns \c v to the element handled by \c handle & updates the priority queue.
*
* \b Complexity: Logarithmic (amortized).
*
* \b Note: The new value is expected to be less than the current one
* */
void decrease (handle_type handle, const_reference v)
{
BOOST_STATIC_ASSERT(is_mutable);
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 (amortized).
*
* \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)
{
BOOST_STATIC_ASSERT(is_mutable);
node_pointer this_node = handle.node_;
unlink_node(this_node);
this_node->children.assign(0);
this_node->set_parent(NULL);
merge_node(this_node);
}
private:
#if !defined(BOOST_DOXYGEN_INVOKED)
struct push_void
{
static void push(skew_heap * self, const_reference v)
{
self->push_internal(v);
}
#if defined(BOOST_HAS_RVALUE_REFS) && !defined(BOOST_NO_VARIADIC_TEMPLATES)
template <class... Args>
static void emplace(skew_heap * self, Args&&... args)
{
self->emplace_internal(std::forward<Args>(args)...);
}
#endif
};
struct push_handle
{
static handle_type push(skew_heap * self, const_reference v)
{
return handle_type(self->push_internal(v));
}
#if defined(BOOST_HAS_RVALUE_REFS) && !defined(BOOST_NO_VARIADIC_TEMPLATES)
template <class... Args>
static handle_type emplace(skew_heap * self, Args&&... args)
{
return handle_type(self->emplace_internal(std::forward<Args>(args)...));
}
#endif
};
node_pointer push_internal(const_reference v)
{
size_holder::increment();
node_pointer n = super_t::allocate(1);
new(n) node(super_t::make_node(v));
merge_node(n);
return n;
}
#if defined(BOOST_HAS_RVALUE_REFS) && !defined(BOOST_NO_VARIADIC_TEMPLATES)
template <class... Args>
node_pointer emplace_internal(Args&&... args)
{
size_holder::increment();
node_pointer n = super_t::allocate(1);
new(n) node(super_t::make_node(std::forward<Args>(args)...));
merge_node(n);
return n;
}
#endif
void unlink_node(node_pointer node)
{
node_pointer parent = node->get_parent();
node_pointer merged_children = merge_children(node);
if (parent) {
if (node == parent->children[0])
parent->children[0] = merged_children;
else
parent->children[1] = merged_children;
}
else
root = merged_children;
}
void clone_tree(skew_heap const & rhs)
{
BOOST_HEAP_ASSERT(root == NULL);
if (rhs.empty())
return;
root = allocator_type::allocate(1);
new(root) node(*rhs.root, static_cast<allocator_type&>(*this), NULL);
}
void merge_node(node_pointer other)
{
BOOST_HEAP_ASSERT(other);
if (root != NULL)
root = merge_nodes(root, other, NULL);
else
root = other;
}
node_pointer merge_nodes(node_pointer node1, node_pointer node2, node_pointer new_parent)
{
if (node1 == NULL) {
if (node2)
node2->set_parent(new_parent);
return node2;
}
if (node2 == NULL) {
node1->set_parent(new_parent);
return node1;
}
node_pointer merged = merge_nodes_recursive(node1, node2, new_parent);
return merged;
}
node_pointer merge_children(node_pointer node)
{
node_pointer parent = node->get_parent();
node_pointer merged_children = merge_nodes(node->children[0], node->children[1], parent);
return merged_children;
}
node_pointer merge_nodes_recursive(node_pointer node1, node_pointer node2, node_pointer new_parent)
{
if (super_t::operator()(node1->value, node2->value))
std::swap(node1, node2);
node * parent = node1;
node * child = node2;
if (parent->children[1]) {
node * merged = merge_nodes(parent->children[1], child, parent);
parent->children[1] = merged;
merged->set_parent(parent);
} else {
parent->children[1] = child;
child->set_parent(parent);
}
std::swap(parent->children[0], parent->children[1]);
parent->set_parent(new_parent);
return parent;
}
void sanity_check(void)
{
#ifdef BOOST_HEAP_SANITYCHECKS
if (root)
BOOST_HEAP_ASSERT( root->template is_heap<super_t>(super_t::value_comp()) );
if (constant_time_size) {
size_type stored_size = size_holder::get_size();
size_type counted_size;
if (root == NULL)
counted_size = 0;
else
counted_size = root->count_children();
BOOST_HEAP_ASSERT(counted_size == stored_size);
}
#endif
}
node_pointer root;
#endif
};
} /* namespace heap */
} /* namespace boost */
#undef BOOST_HEAP_ASSERT
#endif /* BOOST_HEAP_SKEW_HEAP_HPP */