Some Remarks on Deciding Equivalence for Graph-To-Graph Transducers

Authors Mikołaj Bojańczyk, Janusz Schmude

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Mikołaj Bojańczyk
  • Institute of Informatics, University of Warsaw, Poland
Janusz Schmude
  • Institute of Informatics, University of Warsaw, Poland

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Mikołaj Bojańczyk and Janusz Schmude. Some Remarks on Deciding Equivalence for Graph-To-Graph Transducers. In 45th International Symposium on Mathematical Foundations of Computer Science (MFCS 2020). Leibniz International Proceedings in Informatics (LIPIcs), Volume 170, pp. 19:1-19:14, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)


We study the following decision problem: given two mso transductions that input and output graphs of bounded treewidth, decide if they are equivalent, i.e. isomorphic inputs give isomorphic outputs. We do not know how to decide it, but we propose an approach that uses automata manipulating elements of a ring extended with division. The approach works for a variant of the problem, where isomorphism on output graphs is replaced by a relaxation of isomorphism.

Subject Classification

ACM Subject Classification
  • Theory of computation → Formal languages and automata theory
  • equivalence for mso transductions
  • bounded treewidth
  • Hilbert basis theorem


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