Please use this identifier to cite or link to this item: https://doi.org/10.1016/j.jcss.2011.09.002
Title: Ultra-succinct representation of ordered trees with applications
Authors: Jansson, J.
Sadakane, K.
Sung, W.-K. 
Keywords: Compressed suffix tree
Ordered tree
Succinct data structure
Tree degree entropy
Xbw
Issue Date: 2012
Source: Jansson, J., Sadakane, K., Sung, W.-K. (2012). Ultra-succinct representation of ordered trees with applications. Journal of Computer and System Sciences 78 (2) : 619-631. ScholarBank@NUS Repository. https://doi.org/10.1016/j.jcss.2011.09.002
Abstract: There exist two well-known succinct representations of ordered trees: BP (balanced parenthesis) (Munro and Raman, 2001) [20] and DFUDS (depth first unary degree sequence) (Benoit et al., 2005) [1]. Both have size 2n+o(n) bits for n-node trees, which asymptotically matches the information-theoretic lower bound. Importantly, many fundamental operations on trees can be done in constant time on the word RAM when using BP or DFUDS, for example finding the parent, the first child, the next sibling, the number of descendants, etc. Although the space needed to store the BP or DFUDS representation of an ordered tree matches the lower bound, this is not optimal when we consider encodings for certain special classes of trees such as trees in which every internal node has exactly two children. In this paper, we introduce a new, conditional entropy for trees called the tree degree entropy, and give a succinct tree representation with matching size. We call such a representation an ultra-succinct data structure. We show how to modify the DFUDS representation to obtain a "compressed DFUDS", and as a consequence, a tree in which every internal node has exactly two children can be represented in n+o(n) bits. We also describe applications of the compressed DFUDS representation to ultra-succinct compressed suffix trees and labeled trees. © 2011 Elsevier Inc. All Rights Reserved.
Source Title: Journal of Computer and System Sciences
URI: http://scholarbank.nus.edu.sg/handle/10635/39449
ISSN: 00220000
DOI: 10.1016/j.jcss.2011.09.002
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

SCOPUSTM   
Citations

20
checked on Dec 6, 2017

WEB OF SCIENCETM
Citations

16
checked on Nov 22, 2017

Page view(s)

64
checked on Dec 17, 2017

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.