Deciding Confluence of Ground Term Rewrite Systems in Cubic Time

Bertram Felgenhauer
It is well known that the confluence property of ground term rewrite systems (ground TRSs) is decidable in polynomial time. For an efficient implementation, the degree of this polynomial is of great interest. The best complexity bound in the literature is given by Comon, Godoy and Nieuwenhuis (2001), who describe an O(n^5) algorithm, where n is the size of the ground TRS. In this paper we improve this bound to O(n^3). The algorithm has been...