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arXiv · 2212.02380

Complexity of the emptiness problem for graph-walking automata and for tilings with star subgraphs

Olga Martynova
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Abstract

This paper proves the decidability of the emptiness problem for two models which recognize graphs: graph-walking automata, and tilings of graphs by star subgraphs (star automata). Furthermore, it is proved that the non-emptiness problem for graph-walking automata (that is, whether a given automaton accepts at least one graph) is NEXP-complete. For star automata, which generalize nondeterministic tree automata to the case of graphs, it is proved that their non-emptiness problem is NP-complete.

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Olga Martynova. 2022-12-05. Complexity of the emptiness problem for graph-walking automata and for tilings with star subgraphs. https://arxiv.org/abs/2212.02380

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