Improved Algorithm for Reachability in $d$-VASS

Yuxi Fu; Qizhe Yang; Yangluo Zheng

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arXiv · 2404.14781

Improved Algorithm for Reachability in $d$-VASS

Yuxi Fu·Qizhe Yang·Yangluo Zheng

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Abstract

An $\mathsf{F}_{d}$ upper bound for the reachability problem in vector addition systems with states (VASS) in fixed dimension is given, where $\mathsf{F}_d$ is the $d$-th level of the Grzegorczyk hierarchy of complexity classes. The new algorithm combines the idea of the linear path scheme characterization of the reachability in the $2$-dimension VASSes with the general decomposition algorithm by Mayr, Kosaraju and Lambert. The result improves the $\mathsf{F}_{d + 4}$ upper bound due to Leroux and Schmitz (LICS 2019).

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Yuxi Fu, Qizhe Yang, Yangluo Zheng. 2024-04-23. Improved Algorithm for Reachability in $d$-VASS. https://arxiv.org/abs/2404.14781

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