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arXiv · 2307.03561

Complexity of Membership and Non-Emptiness Problems in Unbounded Memory Automata

Clément Bertrand·Cinzia Di Giusto·Hanna Klaudel·Damien Regnault
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Abstract

We study the complexity relationship between three models of unbounded memory automata: nu-automata ($\nu$-A), Layered Memory Automata (LaMA)and History-Register Automata (HRA). These are all extensions of finite state automata with unbounded memory over infinite alphabets. We prove that the membership problem is NP-complete for all of them, while they fall into different classes for what concerns non-emptiness. The problem of non-emptiness is known to be Ackermann-complete for HRA, we prove that it is PSPACE-complete for $\nu$-A.

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Clément Bertrand, Cinzia Di Giusto, Hanna Klaudel, Damien Regnault. 2023-07-07. Complexity of Membership and Non-Emptiness Problems in Unbounded Memory Automata. https://arxiv.org/abs/2307.03561

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