Binary heap implementation in Chicken Scheme.
The binary-heap library is based on the Ocaml heap implementation by
Jean-Christophe Filliatre.
Heaps are encoded as binary trees that have the heap property, namely the value of any node is greater or equal than the nodes in its left and right subtrees.
A binary-heap object is created by procedure make-binary-heap:
make-binary-heap:: KEY-COMPARE-PROC -> HEAP
where KEY-COMPARE-PROC is a user-supplied function that takes two keys and returns a negative, positive, or zero number depending on how the first key compares to the second.
heap-empty? :: HEAP -> BOOL
returns #t if the heap is empty, #f otherwise
heap-get-max :: HEAP -> ELEMENT
returns a (key . value) pair for an association in the heap with the largest key. If the heap is empty, an error is signalled.
heap-size :: HEAP -> INT
returns the size (the number of associations) in the heap
heap-insert :: KEY * VALUE * HEAP -> HEAP
returns a new heap object that contains the given association, while the original heap object is unmodified.
heap-delete-max :: HEAP -> HEAP
removes the max key and the corresponding association from the heap. Returns a (key . value) pair of the removed association. If the heap is empty, an error is signalled.
heap-for-each :: PROC * HEAP -> VOID
applies the given procedure PROC to each (key . value) association of the heap, from the one with the smallest key all the way to the one with the max key, in an ascending order of keys.
heap-fold :: PROC * INIT * HEAP -> RESULT
given the associations in the heap ordered by the descending order of
keys: (key-n . value-n) ... (key-2 . value-2) (key-1 . value-1)
the procedure returns the result of the successive function
applications (PROC value-1 (PROC value-2 ... (PROC value-n INITIAL).
- 2.0 : Removed message-based interface in favor of a simple procedural interface
- 1.2 : Test script updated to return proper exit code
- 1.1 : Documentation converted to wiki format
- 1.0 : Initial release
Copyright 2009-2016 Ivan Raikov
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
A full copy of the GPL license can be found at http://www.gnu.org/licenses/.