Token Games and History-Deterministic Quantitative-Automata

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Boker, Udi, Lehtinen, Karoliina
Format: Preprint
Published: 2021
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917587944734720
author Boker, Udi
Lehtinen, Karoliina
author_facet Boker, Udi
Lehtinen, Karoliina
contents A nondeterministic automaton is history-deterministic if its nondeterminism can be resolved by only considering the prefix of the word read so far. Due to their good compositional properties, history-deterministic automata are useful in solving games and synthesis problems. Deciding whether a given nondeterministic automaton is history-deterministic (the HDness problem) is generally a difficult task, which can involve an exponential procedure, or even be undecidable, as is the case for example with pushdown automata. Token games provide a PTime solution to the HDness problem of Büchi and coBüchi automata, and it is conjectured that 2-token games characterise HDness for all $ω$-regular automata. We extend token games to the quantitative setting and analyse their potential to help deciding HDness of quantitative automata. In particular, we show that 1-token games characterise HDness for all quantitative (and Boolean) automata on finite words, as well as discounted-sum (DSum), Inf and Reachability automata on infinite words, and that 2-token games characterise HDness of LimInf and LimSup automata, as well as Sup automata on infinite words. Using these characterisations, we provide solutions to the HDness problem of Safety, Reachability, Inf and Sup automata on finite and infinite words in PTime, of DSum automata on finite and infinite words in NP$\cap$co-NP, of LimSup automata in quasipolynomial time, and of LimInf automata in exponential time, where the latter two are only polynomial for automata with a logarithmic number of weights.
format Preprint
id arxiv_https___arxiv_org_abs_2110_14308
institution arXiv
publishDate 2021
record_format arxiv
spellingShingle Token Games and History-Deterministic Quantitative-Automata
Boker, Udi
Lehtinen, Karoliina
Formal Languages and Automata Theory
A nondeterministic automaton is history-deterministic if its nondeterminism can be resolved by only considering the prefix of the word read so far. Due to their good compositional properties, history-deterministic automata are useful in solving games and synthesis problems. Deciding whether a given nondeterministic automaton is history-deterministic (the HDness problem) is generally a difficult task, which can involve an exponential procedure, or even be undecidable, as is the case for example with pushdown automata. Token games provide a PTime solution to the HDness problem of Büchi and coBüchi automata, and it is conjectured that 2-token games characterise HDness for all $ω$-regular automata. We extend token games to the quantitative setting and analyse their potential to help deciding HDness of quantitative automata. In particular, we show that 1-token games characterise HDness for all quantitative (and Boolean) automata on finite words, as well as discounted-sum (DSum), Inf and Reachability automata on infinite words, and that 2-token games characterise HDness of LimInf and LimSup automata, as well as Sup automata on infinite words. Using these characterisations, we provide solutions to the HDness problem of Safety, Reachability, Inf and Sup automata on finite and infinite words in PTime, of DSum automata on finite and infinite words in NP$\cap$co-NP, of LimSup automata in quasipolynomial time, and of LimInf automata in exponential time, where the latter two are only polynomial for automata with a logarithmic number of weights.
title Token Games and History-Deterministic Quantitative-Automata
topic Formal Languages and Automata Theory
url https://arxiv.org/abs/2110.14308