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arXiv · 2406.15090

Global One-Counter Tree Automata

Luisa Herrmann·Richard Mörbitz
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Abstract

We introduce global one-counter tree automata (GOCTA) which deviate from usual counter tree automata by working on only one counter which is passed through the tree in lexicographical order, rather than duplicating the counter at every branching position. We compare the capabilities of GOCTA to those of counter tree automata and obtain that their classes of recognizable tree languages are incomparable. Moreover, we show that the emptiness problem of GOCTA is undecidable while, in stark contrast, their membership problem is in P.

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Luisa Herrmann, Richard Mörbitz. 2024-06-21. Global One-Counter Tree Automata. https://arxiv.org/abs/2406.15090

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