7.1.17 Priority Queues
(require 'priority-queue)
This algorithm for priority queues is due to
Introduction to Algorithms
by T. Cormen, C. Leiserson, R. Rivest.
1989 MIT Press.
— Function:
make-heap pred<?
Returns a binary heap suitable which can be used for priority queue
operations.
— Function:
heap-length heap
Returns the number of elements in heap.
— Procedure:
heap-insert! heap item
Inserts item into heap. item can be inserted multiple
times. The value returned is unspecified.
— Procedure:
heap-extract-max! heap
Returns the item which is larger than all others according to the
pred<? argument to make-heap. If there are no items in
heap, an error is signaled.