Chris@16: // boost heap: wrapper for stl heap
Chris@16: //
Chris@16: // Copyright (C) 2010 Tim Blechmann
Chris@16: //
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See
Chris@16: // accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: #ifndef BOOST_HEAP_PRIORITY_QUEUE_HPP
Chris@16: #define BOOST_HEAP_PRIORITY_QUEUE_HPP
Chris@16: 
Chris@16: #include <algorithm>
Chris@16: #include <queue>
Chris@16: #include <utility>
Chris@16: #include <vector>
Chris@16: 
Chris@16: #include <boost/assert.hpp>
Chris@16: 
Chris@16: #include <boost/heap/detail/heap_comparison.hpp>
Chris@16: #include <boost/heap/detail/stable_heap.hpp>
Chris@16: 
Chris@101: #ifdef BOOST_HAS_PRAGMA_ONCE
Chris@101: #pragma once
Chris@101: #endif
Chris@101: 
Chris@101: 
Chris@16: namespace boost  {
Chris@16: namespace heap   {
Chris@16: namespace detail {
Chris@16: 
Chris@16: typedef parameter::parameters<boost::parameter::optional<tag::allocator>,
Chris@16:                               boost::parameter::optional<tag::compare>,
Chris@16:                               boost::parameter::optional<tag::stable>,
Chris@16:                               boost::parameter::optional<tag::stability_counter_type>
Chris@16:                              > priority_queue_signature;
Chris@16: }
Chris@16: 
Chris@16: /**
Chris@16:  * \class priority_queue
Chris@16:  * \brief priority queue, based on stl heap functions
Chris@16:  *
Chris@16:  * The priority_queue class is a wrapper for the stl heap functions.<br>
Chris@16:  * The template parameter T is the type to be managed by the container.
Chris@16:  * The user can specify additional options and if no options are provided default options are used.
Chris@16:  *
Chris@16:  * The container supports the following options:
Chris@16:  * - \c boost::heap::compare<>, defaults to \c compare<std::less<T> >
Chris@16:  * - \c boost::heap::stable<>, defaults to \c stable<false>
Chris@16:  * - \c boost::heap::stability_counter_type<>, defaults to \c stability_counter_type<boost::uintmax_t>
Chris@16:  * - \c boost::heap::allocator<>, defaults to \c allocator<std::allocator<T> >
Chris@16:  *
Chris@16:  */
Chris@16: #ifdef BOOST_DOXYGEN_INVOKED
Chris@16: template<class T, class ...Options>
Chris@16: #else
Chris@16: template <typename T,
Chris@16:           class A0 = boost::parameter::void_,
Chris@16:           class A1 = boost::parameter::void_,
Chris@16:           class A2 = boost::parameter::void_,
Chris@16:           class A3 = boost::parameter::void_
Chris@16:          >
Chris@16: #endif
Chris@16: class priority_queue:
Chris@16:     private detail::make_heap_base<T, typename detail::priority_queue_signature::bind<A0, A1, A2, A3>::type, false>::type
Chris@16: {
Chris@16:     typedef detail::make_heap_base<T, typename detail::priority_queue_signature::bind<A0, A1, A2, A3>::type, false> heap_base_maker;
Chris@16: 
Chris@16:     typedef typename heap_base_maker::type super_t;
Chris@16:     typedef typename super_t::internal_type internal_type;
Chris@16:     typedef typename heap_base_maker::allocator_argument::template rebind<internal_type>::other internal_type_allocator;
Chris@16:     typedef std::vector<internal_type, internal_type_allocator> container_type;
Chris@16: 
Chris@16:     template <typename Heap1, typename Heap2>
Chris@16:     friend struct detail::heap_merge_emulate;
Chris@16: 
Chris@16:     container_type q_;
Chris@16: 
Chris@16: #ifndef BOOST_DOXYGEN_INVOKED
Chris@16:     struct implementation_defined:
Chris@16:         detail::extract_allocator_types<typename heap_base_maker::allocator_argument>
Chris@16:     {
Chris@16:         typedef typename heap_base_maker::compare_argument value_compare;
Chris@16:         typedef detail::stable_heap_iterator<T, typename container_type::const_iterator, super_t> iterator;
Chris@16:         typedef iterator const_iterator;
Chris@16:         typedef typename container_type::allocator_type allocator_type;
Chris@16:     };
Chris@16: #endif
Chris@16: 
Chris@16: public:
Chris@16:     typedef T value_type;
Chris@16:     typedef typename implementation_defined::size_type size_type;
Chris@16:     typedef typename implementation_defined::difference_type difference_type;
Chris@16:     typedef typename implementation_defined::value_compare value_compare;
Chris@16:     typedef typename implementation_defined::allocator_type allocator_type;
Chris@16:     typedef typename implementation_defined::reference reference;
Chris@16:     typedef typename implementation_defined::const_reference const_reference;
Chris@16:     typedef typename implementation_defined::pointer pointer;
Chris@16:     typedef typename implementation_defined::const_pointer const_pointer;
Chris@16:     /**
Chris@16:      * \b Note: The iterator does not traverse the priority queue in order of the priorities.
Chris@16:      * */
Chris@16:     typedef typename implementation_defined::iterator iterator;
Chris@16:     typedef typename implementation_defined::const_iterator const_iterator;
Chris@16: 
Chris@16:     static const bool constant_time_size = true;
Chris@16:     static const bool has_ordered_iterators = false;
Chris@16:     static const bool is_mergable = false;
Chris@16:     static const bool is_stable = heap_base_maker::is_stable;
Chris@16:     static const bool has_reserve = true;
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: constructs an empty priority queue.
Chris@16:      *
Chris@16:      * \b Complexity: Constant.
Chris@16:      *
Chris@16:      * */
Chris@16:     explicit priority_queue(value_compare const & cmp = value_compare()):
Chris@16:         super_t(cmp)
Chris@16:     {}
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: copy-constructs priority queue from rhs.
Chris@16:      *
Chris@16:      * \b Complexity: Linear.
Chris@16:      *
Chris@16:      * */
Chris@16:     priority_queue (priority_queue const & rhs):
Chris@16:         super_t(rhs), q_(rhs.q_)
Chris@16:     {}
Chris@16: 
Chris@16: #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
Chris@16:     /**
Chris@16:      * \b Effects: C++11-style move constructor.
Chris@16:      *
Chris@16:      * \b Complexity: Constant.
Chris@16:      *
Chris@16:      * \b Note: Only available, if BOOST_NO_CXX11_RVALUE_REFERENCES is not defined
Chris@16:      * */
Chris@16:     priority_queue(priority_queue && rhs):
Chris@16:         super_t(std::move(rhs)), q_(std::move(rhs.q_))
Chris@16:     {}
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: C++11-style move assignment.
Chris@16:      *
Chris@16:      * \b Complexity: Constant.
Chris@16:      *
Chris@16:      * \b Note: Only available, if BOOST_NO_CXX11_RVALUE_REFERENCES is not defined
Chris@16:      * */
Chris@16:     priority_queue & operator=(priority_queue && rhs)
Chris@16:     {
Chris@16:         super_t::operator=(std::move(rhs));
Chris@16:         q_ = std::move(rhs.q_);
Chris@16:         return *this;
Chris@16:     }
Chris@16: #endif
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Assigns priority queue from rhs.
Chris@16:      *
Chris@16:      * \b Complexity: Linear.
Chris@16:      *
Chris@16:      * */
Chris@16:     priority_queue & operator=(priority_queue const & rhs)
Chris@16:     {
Chris@16:         static_cast<super_t&>(*this) = static_cast<super_t const &>(rhs);
Chris@16:         q_ = rhs.q_;
Chris@16:         return *this;
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Returns true, if the priority queue contains no elements.
Chris@16:      *
Chris@16:      * \b Complexity: Constant.
Chris@16:      *
Chris@16:      * */
Chris@16:     bool empty(void) const
Chris@16:     {
Chris@16:         return q_.empty();
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Returns the number of elements contained in the priority queue.
Chris@16:      *
Chris@16:      * \b Complexity: Constant.
Chris@16:      *
Chris@16:      * */
Chris@16:     size_type size(void) const
Chris@16:     {
Chris@16:         return q_.size();
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Returns the maximum number of elements the priority queue can contain.
Chris@16:      *
Chris@16:      * \b Complexity: Constant.
Chris@16:      *
Chris@16:      * */
Chris@16:     size_type max_size(void) const
Chris@16:     {
Chris@16:         return q_.max_size();
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Removes all elements from the priority queue.
Chris@16:      *
Chris@16:      * \b Complexity: Linear.
Chris@16:      *
Chris@16:      * */
Chris@16:     void clear(void)
Chris@16:     {
Chris@16:         q_.clear();
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Returns allocator.
Chris@16:      *
Chris@16:      * \b Complexity: Constant.
Chris@16:      *
Chris@16:      * */
Chris@16:     allocator_type get_allocator(void) const
Chris@16:     {
Chris@16:         return q_.get_allocator();
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Returns a const_reference to the maximum element.
Chris@16:      *
Chris@16:      * \b Complexity: Constant.
Chris@16:      *
Chris@16:      * */
Chris@16:     const_reference top(void) const
Chris@16:     {
Chris@16:         BOOST_ASSERT(!empty());
Chris@16:         return super_t::get_value(q_.front());
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Adds a new element to the priority queue.
Chris@16:      *
Chris@16:      * \b Complexity: Logarithmic (amortized). Linear (worst case).
Chris@16:      *
Chris@16:      * */
Chris@16:     void push(value_type const & v)
Chris@16:     {
Chris@16:         q_.push_back(super_t::make_node(v));
Chris@16:         std::push_heap(q_.begin(), q_.end(), static_cast<super_t const &>(*this));
Chris@16:     }
Chris@16: 
Chris@16: #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
Chris@16:     /**
Chris@16:      * \b Effects: Adds a new element to the priority queue. The element is directly constructed in-place.
Chris@16:      *
Chris@16:      * \b Complexity: Logarithmic (amortized). Linear (worst case).
Chris@16:      *
Chris@16:      * */
Chris@16:     template <class... Args>
Chris@16:     void emplace(Args&&... args)
Chris@16:     {
Chris@16:         q_.emplace_back(super_t::make_node(std::forward<Args>(args)...));
Chris@16:         std::push_heap(q_.begin(), q_.end(), static_cast<super_t const &>(*this));
Chris@16:     }
Chris@16: #endif
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Removes the top element from the priority queue.
Chris@16:      *
Chris@16:      * \b Complexity: Logarithmic (amortized). Linear (worst case).
Chris@16:      *
Chris@16:      * */
Chris@16:     void pop(void)
Chris@16:     {
Chris@16:         BOOST_ASSERT(!empty());
Chris@16:         std::pop_heap(q_.begin(), q_.end(), static_cast<super_t const &>(*this));
Chris@16:         q_.pop_back();
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Swaps two priority queues.
Chris@16:      *
Chris@16:      * \b Complexity: Constant.
Chris@16:      *
Chris@16:      * */
Chris@16:     void swap(priority_queue & rhs)
Chris@16:     {
Chris@16:         super_t::swap(rhs);
Chris@16:         q_.swap(rhs.q_);
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Returns an iterator to the first element contained in the priority queue.
Chris@16:      *
Chris@16:      * \b Complexity: Constant.
Chris@16:      *
Chris@16:      * */
Chris@16:     iterator begin(void) const
Chris@16:     {
Chris@16:         return iterator(q_.begin());
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Returns an iterator to the end of the priority queue.
Chris@16:      *
Chris@16:      * \b Complexity: Constant.
Chris@16:      *
Chris@16:      * */
Chris@16:     iterator end(void) const
Chris@16:     {
Chris@16:         return iterator(q_.end());
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effects: Reserves memory for element_count elements
Chris@16:      *
Chris@16:      * \b Complexity: Linear.
Chris@16:      *
Chris@16:      * \b Node: Invalidates iterators
Chris@16:      *
Chris@16:      * */
Chris@16:     void reserve(size_type element_count)
Chris@16:     {
Chris@16:         q_.reserve(element_count);
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Effect: Returns the value_compare object used by the priority queue
Chris@16:      *
Chris@16:      * */
Chris@16:     value_compare const & value_comp(void) const
Chris@16:     {
Chris@16:         return super_t::value_comp();
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Returns: Element-wise comparison of heap data structures
Chris@16:      *
Chris@16:      * \b Requirement: the \c value_compare object of both heaps must match.
Chris@16:      *
Chris@16:      * */
Chris@16:     template <typename HeapType>
Chris@16:     bool operator<(HeapType const & rhs) const
Chris@16:     {
Chris@16:         return detail::heap_compare(*this, rhs);
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Returns: Element-wise comparison of heap data structures
Chris@16:      *
Chris@16:      * \b Requirement: the \c value_compare object of both heaps must match.
Chris@16:      *
Chris@16:      * */
Chris@16:     template <typename HeapType>
Chris@16:     bool operator>(HeapType const & rhs) const
Chris@16:     {
Chris@16:         return detail::heap_compare(rhs, *this);
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Returns: Element-wise comparison of heap data structures
Chris@16:      *
Chris@16:      * \b Requirement: the \c value_compare object of both heaps must match.
Chris@16:      *
Chris@16:      * */
Chris@16:     template <typename HeapType>
Chris@16:     bool operator>=(HeapType const & rhs) const
Chris@16:     {
Chris@16:         return !operator<(rhs);
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * \b Returns: Element-wise comparison of heap data structures
Chris@16:      *
Chris@16:      * \b Requirement: the \c value_compare object of both heaps must match.
Chris@16:      *
Chris@16:      * */
Chris@16:     template <typename HeapType>
Chris@16:     bool operator<=(HeapType const & rhs) const
Chris@16:     {
Chris@16:         return !operator>(rhs);
Chris@16:     }
Chris@16: 
Chris@16:     /** \brief Equivalent comparison
Chris@16:      * \b Returns: True, if both heap data structures are equivalent.
Chris@16:      *
Chris@16:      * \b Requirement: the \c value_compare object of both heaps must match.
Chris@16:      *
Chris@16:      * */
Chris@16:     template <typename HeapType>
Chris@16:     bool operator==(HeapType const & rhs) const
Chris@16:     {
Chris@16:         return detail::heap_equality(*this, rhs);
Chris@16:     }
Chris@16: 
Chris@16:     /** \brief Equivalent comparison
Chris@16:      * \b Returns: True, if both heap data structures are not equivalent.
Chris@16:      *
Chris@16:      * \b Requirement: the \c value_compare object of both heaps must match.
Chris@16:      *
Chris@16:      * */
Chris@16:     template <typename HeapType>
Chris@16:     bool operator!=(HeapType const & rhs) const
Chris@16:     {
Chris@16:         return !(*this == rhs);
Chris@16:     }
Chris@16: };
Chris@16: 
Chris@16: } /* namespace heap */
Chris@16: } /* namespace boost */
Chris@16: 
Chris@16: #endif /* BOOST_HEAP_PRIORITY_QUEUE_HPP */