Deciding Confluence of Certain Term Rewriting Systems in Polynomial Time

Ashish Tiwari

To appear in LICS 2002, which is being held as part of FLoC 2002, Copenhagen, Denmark, July 20--Aug 1, 2002.

Abstract

We present a polynomial time algorithm for deciding confluence of ground term rewrite systems. We generalize the decision procedure to get a polynomial time algorithm, assuming that the maximum arity of a symbol in the signature is a constant, for deciding confluence of rewrite systems where each rule contains a shallow linear term on one side and a ground term on the other. The existence of a polynomial time algorithm for deciding confluence of ground rewrite systems was open for a long time and was independently solved only recently by Comon, Godoy, and Nieuwenhuis [FoCS 2001]. Our decision procedure is based on the concepts of abstract congruence closure and abstract rewrite closure, which have been described by Bachmair and Tiwari [CADE 2000] and Tiwari [FSTTCS 2001], respectively.

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See also the journal version of this paper (co-authored with Godoy and Nieuwenhuis): click here.

Slides

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BibTeX Entry


@inproceedings{Tiwari02:FLoC,
	TITLE = {Deciding Confluence of Certain Term Rewriting Systems in Polynomial Time},
	AUTHOR = {A. Tiwari},
	BOOKTITLE = {{IEEE} Symposium on Logic in Computer Science, LICS 2002},
	EDITOR = {Gordon Plotkin},
	PAGES = {447--456},
	PUBLISHER = {IEEE Society},
	MONTH = July,
	YEAR = 2002
}


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