A priority queue with elements of type a. Supports extracting the maximum element. Implemented as a wrapper around MinQueue.

\(O(1)\). The empty priority queue.

\(O(1)\). Is this the empty priority queue?

\(O(1)\). The number of elements in the queue.

\(O(1)\). Returns the maximum element of the queue. Throws an error on an empty queue.

\(O(1)\). The top (maximum) element of the queue, if there is one.

\(O(\log n)\). Deletes the maximum element of the queue. Does nothing on an empty queue.

\(O(\log n)\). Extracts the maximum element of the queue. Throws an error on an empty queue.

\(O(\log n)\). Delete the top (maximum) element of the sequence, if there is one.

\(O(\log n)\). Extract the top (maximum) element of the sequence, if there is one.

\(O(1)\). Construct a priority queue with a single element.

\(O(1)\). Insert an element into the priority queue.

\(O(\log min(n_1,n_2))\). Take the union of two priority queues.

Takes the union of a list of priority queues. Equivalent to foldl union empty.

\(O(k \log n)\)/. Returns the (k+1)th largest element of the queue.

\(O(k \log n)\)/. Returns the list of the k largest elements of the queue, in descending order, or all elements of the queue, if k >= n.

\(O(k \log n)\)/. Returns the queue with the k largest elements deleted, or the empty queue if k >= n.

\(O(k \log n)\)/. Equivalent to (take k queue, drop k queue).

takeWhile, applied to a predicate p and a queue queue, returns the longest prefix (possibly empty) of queue of elements that satisfy p.

dropWhile p queue returns the queue remaining after takeWhile p queue.

span, applied to a predicate p and a queue queue, returns a tuple where first element is longest prefix (possibly empty) of queue of elements that satisfy p and second element is the remainder of the queue.

break, applied to a predicate p and a queue queue, returns a tuple where first element is longest prefix (possibly empty) of queue of elements that do not satisfy p and second element is the remainder of the queue.

\(O(n)\). Returns a queue of those elements which satisfy the predicate.

\(O(n)\). Returns a pair of queues, where the left queue contains those elements that satisfy the predicate, and the right queue contains those that do not.

\(O(n)\). Maps a function over the elements of the queue, and collects the Just values.

\(O(n)\). Maps a function over the elements of the queue, and separates the Left and Right values.

\(O(n)\). Creates a new priority queue containing the images of the elements of this queue. Equivalent to fromList . map f . toList.

\(O(n \log n)\). Performs a right-fold on the elements of a priority queue in ascending order. foldrAsc f z q == foldlDesc (flip f) z q.

\(O(n \log n)\). Performs a left-fold on the elements of a priority queue in descending order. foldlAsc f z q == foldrDesc (flip f) z q.

\(O(n \log n)\). Performs a right-fold on the elements of a priority queue in descending order.

\(O(n \log n)\). Performs a left-fold on the elements of a priority queue in descending order.

\(O(n \log n)\). Returns the elements of the priority queue in ascending order. Equivalent to toDescList.

If the order of the elements is irrelevant, consider using toListU.

\(O(n \log n)\). Extracts the elements of the priority queue in ascending order.

\(O(n \log n)\). Extracts the elements of the priority queue in descending order.

\(O(n \log n)\). Constructs a priority queue from an unordered list.

\(O(n)\). Constructs a priority queue from an ascending list. Warning: Does not check the precondition.

\(O(n)\). Constructs a priority queue from a descending list. Warning: Does not check the precondition.

\(O(n)\). Assumes that the function it is given is monotonic, and applies this function to every element of the priority queue. Does not check the precondition.

\(O(n)\). Unordered right fold on a priority queue.

\(O(n)\). Unordered left fold on a priority queue. This is rarely what you want; foldrU and foldlU' are more likely to perform well.

\(O(n)\). Unordered strict left fold on a priority queue.

Since: 1.4.2

\(O(n)\). Unordered monoidal fold on a priority queue.

Since: 1.4.2

Equivalent to toListU.

\(O(n)\). Returns a list of the elements of the priority queue, in no particular order.

\(O(n)\). Constructs a priority queue from the keys of a MaxPQueue.

\(O(\log n)\). seqSpine q r forces the spine of q and returns r.

Note: The spine of a MaxQueue is stored somewhat lazily. Most operations take great care to prevent chains of thunks from accumulating along the spine to the detriment of performance. However, mapU can leave expensive thunks in the structure and repeated applications of that function can create thunk chains.