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Class template priority_queue

boost::heap::priority_queue — priority queue, based on stl heap functions

Synopsis

// In header: <boost/heap/priority_queue.hpp>

template<typename T, class... Options> 
class priority_queue {
public:
  // types
  typedef T                                       value_type;     
  typedef implementation_defined::size_type       size_type;      
  typedef implementation_defined::difference_type difference_type;
  typedef implementation_defined::value_compare   value_compare;  
  typedef implementation_defined::allocator_type  allocator_type; 
  typedef implementation_defined::reference       reference;      
  typedef implementation_defined::const_reference const_reference;
  typedef implementation_defined::pointer         pointer;        
  typedef implementation_defined::const_pointer   const_pointer;  
  typedef implementation_defined::iterator        iterator;       
  typedef implementation_defined::const_iterator  const_iterator; 

  // construct/copy/destruct
  explicit priority_queue(value_compare const & = value_compare());
  priority_queue(priority_queue const &);
  priority_queue(priority_queue &&);
  priority_queue& operator=(priority_queue &&);
  priority_queue& operator=(priority_queue const &);

  // public member functions
  bool empty(void) const;
  size_type size(void) const;
  size_type max_size(void) const;
  void clear(void);
  allocator_type get_allocator(void) const;
  const_reference top(void) const;
  void push(value_type const &);
  template<class... Args> void emplace(Args &&...);
  void pop(void);
  void swap(priority_queue &);
  iterator begin(void) const;
  iterator end(void) const;
  void reserve(size_type);
  value_compare const & value_comp(void) const;
  template<typename HeapType> bool operator<(HeapType const &) const;
  template<typename HeapType> bool operator>(HeapType const &) const;
  template<typename HeapType> bool operator>=(HeapType const &) const;
  template<typename HeapType> bool operator<=(HeapType const &) const;
  template<typename HeapType> bool operator==(HeapType const &) const;
  template<typename HeapType> bool operator!=(HeapType const &) const;

  // public data members
  static const bool constant_time_size;
  static const bool has_ordered_iterators;
  static const bool is_mergable;
  static const bool is_stable;
  static const bool has_reserve;
};

Description

The priority_queue class is a wrapper for the stl heap functions.
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:

  • boost::heap::compare<>, defaults to compare<std::less<T> >

  • boost::heap::stable<>, defaults to stable<false>

  • boost::heap::stability_counter_type<>, defaults to stability_counter_type<boost::uintmax_t>

  • boost::heap::allocator<>, defaults to allocator<std::allocator<T> >

priority_queue public types

  1. typedef implementation_defined::iterator iterator;

    Note: The iterator does not traverse the priority queue in order of the priorities.

priority_queue public construct/copy/destruct

  1. explicit priority_queue(value_compare const & cmp = value_compare());

    Effects: constructs an empty priority queue.

    Complexity: Constant.

  2. priority_queue(priority_queue const & rhs);

    Effects: copy-constructs priority queue from rhs.

    Complexity: Linear.

  3. priority_queue(priority_queue && rhs);

    Effects: C++11-style move constructor.

    Complexity: Constant.

    Note: Only available, if BOOST_HAS_RVALUE_REFS is defined

  4. priority_queue& operator=(priority_queue && rhs);

    Effects: C++11-style move assignment.

    Complexity: Constant.

    Note: Only available, if BOOST_HAS_RVALUE_REFS is defined

  5. priority_queue& operator=(priority_queue const & rhs);

    Effects: Assigns priority queue from rhs.

    Complexity: Linear.

priority_queue public member functions

  1. bool empty(void) const;

    Effects: Returns true, if the priority queue contains no elements.

    Complexity: Constant.

  2. size_type size(void) const;

    Effects: Returns the number of elements contained in the priority queue.

    Complexity: Constant.

  3. size_type max_size(void) const;

    Effects: Returns the maximum number of elements the priority queue can contain.

    Complexity: Constant.

  4. void clear(void);

    Effects: Removes all elements from the priority queue.

    Complexity: Linear.

  5. allocator_type get_allocator(void) const;

    Effects: Returns allocator.

    Complexity: Constant.

  6. const_reference top(void) const;

    Effects: Returns a const_reference to the maximum element.

    Complexity: Constant.

  7. void push(value_type const & v);

    Effects: Adds a new element to the priority queue.

    Complexity: Logarithmic (amortized). Linear (worst case).

  8. template<class... Args> void emplace(Args &&... args);

    Effects: Adds a new element to the priority queue. The element is directly constructed in-place.

    Complexity: Logarithmic (amortized). Linear (worst case).

  9. void pop(void);

    Effects: Removes the top element from the priority queue.

    Complexity: Logarithmic (amortized). Linear (worst case).

  10. void swap(priority_queue & rhs);

    Effects: Swaps two priority queues.

    Complexity: Constant.

  11. iterator begin(void) const;

    Effects: Returns an iterator to the first element contained in the priority queue.

    Complexity: Constant.

  12. iterator end(void) const;

    Effects: Returns an iterator to the end of the priority queue.

    Complexity: Constant.

  13. void reserve(size_type element_count);

    Effects: Reserves memory for element_count elements

    Complexity: Linear.

    Node: Invalidates iterators

  14. value_compare const & value_comp(void) const;

    Effect: Returns the value_compare object used by the priority queue

  15. template<typename HeapType> bool operator<(HeapType const & rhs) const;

    Returns: Element-wise comparison of heap data structures

    Requirement: the value_compare object of both heaps must match.

  16. template<typename HeapType> bool operator>(HeapType const & rhs) const;

    Returns: Element-wise comparison of heap data structures

    Requirement: the value_compare object of both heaps must match.

  17. template<typename HeapType> bool operator>=(HeapType const & rhs) const;

    Returns: Element-wise comparison of heap data structures

    Requirement: the value_compare object of both heaps must match.

  18. template<typename HeapType> bool operator<=(HeapType const & rhs) const;

    Returns: Element-wise comparison of heap data structures

    Requirement: the value_compare object of both heaps must match.

  19. template<typename HeapType> bool operator==(HeapType const & rhs) const;
    Equivalent comparison Returns: True, if both heap data structures are equivalent.

    Requirement: the value_compare object of both heaps must match.

  20. template<typename HeapType> bool operator!=(HeapType const & rhs) const;
    Equivalent comparison Returns: True, if both heap data structures are not equivalent.

    Requirement: the value_compare object of both heaps must match.


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