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arXiv · 2202.03730

Computing H-Partitions in ASP and Datalog

Abstract

A $H$-partition of a finite undirected simple graph $G$ is a labeling of $G$'s vertices such that the constraints expressed by the model graph $H$ are satisfied. For every model graph $H$, it can be decided in non-deterministic polynomial time whether a given input graph $G$ admits a $H$-partition. Moreover, it has been shown by Dantas et al. that for most model graphs, this decision problem is in deterministic polynomial time. In this paper, we show that these polynomial-time algorithms for finding $H$-partitions can be expressed in Datalog with stratified negation. Moreover, using the answer set solver Clingo, we have conducted experiments to compare straightforward guess-and-check programs with Datalog programs. Our experiments indicate that in Clingo, guess-and-check programs run faster than their equivalent Datalog programs.

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Chloé Capon, Nicolas Lecomte, Jef Wijsen. 2022-02-08. Computing H-Partitions in ASP and Datalog. https://arxiv.org/abs/2202.03730

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