ecency-mobile/ios/Pods/boost-for-react-native/boost/heap/pairing_heap.hpp

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22 KiB
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// boost heap: pairing 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_PAIRING_HEAP_HPP
#define BOOST_HEAP_PAIRING_HEAP_HPP
#include <algorithm>
#include <utility>
#include <vector>
#include <boost/assert.hpp>
#include <boost/heap/detail/heap_comparison.hpp>
#include <boost/heap/detail/heap_node.hpp>
#include <boost/heap/policies.hpp>
#include <boost/heap/detail/stable_heap.hpp>
#include <boost/heap/detail/tree_iterator.hpp>
#ifdef BOOST_HAS_PRAGMA_ONCE
#pragma once
#endif
#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>
> pairing_heap_signature;
template <typename T, typename Parspec>
struct make_pairing_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 heap_node<typename base_type::internal_type, false> 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)
{}
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
type(type const & rhs):
base_type(rhs), allocator_type(rhs)
{}
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<const allocator_type&>(rhs));
return *this;
}
#endif
};
};
}
/**
* \class pairing_heap
* \brief pairing heap
*
* Pairing heaps are self-adjusting binary heaps. Although design and implementation are rather simple,
* the complexity analysis is yet unsolved. For details, consult:
*
* Pettie, Seth (2005), "Towards a final analysis of pairing heaps",
* Proc. 46th Annual IEEE Symposium on Foundations of Computer Science, pp. 174-183
*
* 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>
*
*
*/
#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_
>
#endif
class pairing_heap:
private detail::make_pairing_heap_base<T,
typename detail::pairing_heap_signature::bind<A0, A1, A2, A3, A4>::type
>::type
{
typedef typename detail::pairing_heap_signature::bind<A0, A1, A2, A3, A4>::type bound_args;
typedef detail::make_pairing_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;
private:
template <typename Heap1, typename Heap2>
friend struct heap_merge_emulate;
#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::heap_node_list node_list_type;
typedef typename node_list_type::iterator node_list_iterator;
typedef typename node_list_type::const_iterator node_list_const_iterator;
typedef typename base_maker::node_type node;
typedef detail::value_extractor<value_type, internal_type, super_t> value_extractor;
typedef typename super_t::internal_compare internal_compare;
typedef detail::node_handle<node_pointer, super_t, reference> handle_type;
typedef detail::tree_iterator<node,
const value_type,
allocator_type,
value_extractor,
detail::pointer_to_reference<node>,
false,
false,
value_compare
> iterator;
typedef iterator const_iterator;
typedef detail::tree_iterator<node,
const value_type,
allocator_type,
value_extractor,
detail::pointer_to_reference<node>,
false,
true,
value_compare
> ordered_iterator;
};
typedef typename implementation_defined::node node;
typedef typename implementation_defined::node_pointer node_pointer;
typedef typename implementation_defined::node_list_type node_list_type;
typedef typename implementation_defined::node_list_iterator node_list_iterator;
typedef typename implementation_defined::node_list_const_iterator node_list_const_iterator;
typedef typename implementation_defined::internal_compare internal_compare;
typedef boost::intrusive::list<detail::heap_node_base<true>,
boost::intrusive::constant_time_size<false>
> node_child_list;
#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;
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;
/// \copydoc boost::heap::priority_queue::priority_queue(value_compare const &)
explicit pairing_heap(value_compare const & cmp = value_compare()):
super_t(cmp), root(NULL)
{}
/// \copydoc boost::heap::priority_queue::priority_queue(priority_queue const &)
pairing_heap(pairing_heap const & rhs):
super_t(rhs), root(NULL)
{
if (rhs.empty())
return;
clone_tree(rhs);
size_holder::set_size(rhs.get_size());
}
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
/// \copydoc boost::heap::priority_queue::priority_queue(priority_queue &&)
pairing_heap(pairing_heap && rhs):
super_t(std::move(rhs)), root(rhs.root)
{
rhs.root = NULL;
}
/// \copydoc boost::heap::priority_queue::operator=(priority_queue &&)
pairing_heap & operator=(pairing_heap && rhs)
{
super_t::operator=(std::move(rhs));
root = rhs.root;
rhs.root = NULL;
return *this;
}
#endif
/// \copydoc boost::heap::priority_queue::operator=(priority_queue const & rhs)
pairing_heap & operator=(pairing_heap const & rhs)
{
clear();
size_holder::set_size(rhs.get_size());
static_cast<super_t&>(*this) = rhs;
clone_tree(rhs);
return *this;
}
~pairing_heap(void)
{
while (!empty())
pop();
}
/// \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 detail::count_nodes(root);
}
/// \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(pairing_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: Adds a new element to the priority queue. Returns handle to element
*
* \cond
* \b Complexity: \f$2^2log(log(N))\f$ (amortized).
* \endcond
*
* \b Complexity: 2**2*log(log(N)) (amortized).
*
* */
handle_type push(value_type const & v)
{
size_holder::increment();
node_pointer n = allocator_type::allocate(1);
new(n) node(super_t::make_node(v));
merge_node(n);
return handle_type(n);
}
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
/**
* \b Effects: Adds a new element to the priority queue. The element is directly constructed in-place. Returns handle to element.
*
* \cond
* \b Complexity: \f$2^2log(log(N))\f$ (amortized).
* \endcond
*
* \b Complexity: 2**2*log(log(N)) (amortized).
*
* */
template <class... Args>
handle_type emplace(Args&&... args)
{
size_holder::increment();
node_pointer n = allocator_type::allocate(1);
new(n) node(super_t::make_node(std::forward<Args>(args)...));
merge_node(n);
return handle_type(n);
}
#endif
/**
* \b Effects: Removes the top element from the priority queue.
*
* \b Complexity: Logarithmic (amortized).
*
* */
void pop(void)
{
BOOST_ASSERT(!empty());
erase(handle_type(root));
}
/**
* \b Effects: Assigns \c v to the element handled by \c handle & updates the priority queue.
*
* \cond
* \b Complexity: \f$2^2log(log(N))\f$ (amortized).
* \endcond
*
* \b Complexity: 2**2*log(log(N)) (amortized).
*
* */
void update (handle_type handle, const_reference v)
{
handle.node_->value = super_t::make_node(v);
update(handle);
}
/**
* \b Effects: Updates the heap after the element handled by \c handle has been changed.
*
* \cond
* \b Complexity: \f$2^2log(log(N))\f$ (amortized).
* \endcond
*
* \b Complexity: 2**2*log(log(N)) (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)
{
node_pointer n = handle.node_;
n->unlink();
if (!n->children.empty())
n = merge_nodes(n, merge_node_list(n->children));
if (n != root)
merge_node(n);
}
/**
* \b Effects: Assigns \c v to the element handled by \c handle & updates the priority queue.
*
* \cond
* \b Complexity: \f$2^2log(log(N))\f$ (amortized).
* \endcond
*
* \b Complexity: 2**2*log(log(N)) (amortized).
*
* \b Note: The new value is expected to be greater than the current one
* */
void increase (handle_type handle, const_reference v)
{
update(handle, v);
}
/**
* \b Effects: Updates the heap after the element handled by \c handle has been changed.
*
* \cond
* \b Complexity: \f$2^2log(log(N))\f$ (amortized).
* \endcond
*
* \b Complexity: 2**2*log(log(N)) (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)
{
update(handle);
}
/**
* \b Effects: Assigns \c v to the element handled by \c handle & updates the priority queue.
*
* \cond
* \b Complexity: \f$2^2log(log(N))\f$ (amortized).
* \endcond
*
* \b Complexity: 2**2*log(log(N)) (amortized).
*
* \b Note: The new value is expected to be less than the current one
* */
void decrease (handle_type handle, const_reference v)
{
update(handle, v);
}
/**
* \b Effects: Updates the heap after the element handled by \c handle has been changed.
*
* \cond
* \b Complexity: \f$2^2log(log(N))\f$ (amortized).
* \endcond
*
* \b Complexity: 2**2*log(log(N)) (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)
{
update(handle);
}
/**
* \b Effects: Removes the element handled by \c handle from the priority_queue.
*
* \cond
* \b Complexity: \f$2^2log(log(N))\f$ (amortized).
* \endcond
*
* \b Complexity: 2**2*log(log(N)) (amortized).
* */
void erase(handle_type handle)
{
node_pointer n = handle.node_;
if (n != root) {
n->unlink();
if (!n->children.empty())
merge_node(merge_node_list(n->children));
} else {
if (!n->children.empty())
root = merge_node_list(n->children);
else
root = NULL;
}
size_holder::decrement();
n->~node();
allocator_type::deallocate(n, 1);
}
/// \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(super_t::value_comp());
}
/// \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(NULL, super_t::value_comp());
}
/// \copydoc boost::heap::d_ary_heap_mutable::s_handle_from_iterator
static handle_type s_handle_from_iterator(iterator const & it)
{
node * ptr = const_cast<node *>(it.get_node());
return handle_type(ptr);
}
/**
* \b Effects: Merge all elements from rhs into this
*
* \cond
* \b Complexity: \f$2^2log(log(N))\f$ (amortized).
* \endcond
*
* \b Complexity: 2**2*log(log(N)) (amortized).
*
* */
void merge(pairing_heap & rhs)
{
if (rhs.empty())
return;
merge_node(rhs.root);
size_holder::add(rhs.get_size());
rhs.set_size(0);
rhs.root = NULL;
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);
}
private:
#if !defined(BOOST_DOXYGEN_INVOKED)
void clone_tree(pairing_heap const & rhs)
{
BOOST_HEAP_ASSERT(root == NULL);
if (rhs.empty())
return;
root = allocator_type::allocate(1);
new(root) node(static_cast<node const &>(*rhs.root), static_cast<allocator_type&>(*this));
}
void merge_node(node_pointer other)
{
BOOST_HEAP_ASSERT(other);
if (root != NULL)
root = merge_nodes(root, other);
else
root = other;
}
node_pointer merge_node_list(node_child_list & children)
{
BOOST_HEAP_ASSERT(!children.empty());
node_pointer merged = merge_first_pair(children);
if (children.empty())
return merged;
node_child_list node_list;
node_list.push_back(*merged);
do {
node_pointer next_merged = merge_first_pair(children);
node_list.push_back(*next_merged);
} while (!children.empty());
return merge_node_list(node_list);
}
node_pointer merge_first_pair(node_child_list & children)
{
BOOST_HEAP_ASSERT(!children.empty());
node_pointer first_child = static_cast<node_pointer>(&children.front());
children.pop_front();
if (children.empty())
return first_child;
node_pointer second_child = static_cast<node_pointer>(&children.front());
children.pop_front();
return merge_nodes(first_child, second_child);
}
node_pointer merge_nodes(node_pointer node1, node_pointer node2)
{
if (super_t::operator()(node1->value, node2->value))
std::swap(node1, node2);
node2->unlink();
node1->children.push_front(*node2);
return node1;
}
node_pointer root;
#endif
};
} /* namespace heap */
} /* namespace boost */
#undef BOOST_HEAP_ASSERT
#endif /* BOOST_HEAP_PAIRING_HEAP_HPP */