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arXiv · 1506.07774

Tightening the Complexity of Equivalence Problems for Commutative Grammars

Christoph Haase·Piotr Hofman
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Abstract

We show that the language equivalence problem for regular and context-free commutative grammars is coNEXP-complete. In addition, our lower bound immediately yields further coNEXP-completeness results for equivalence problems for communication-free Petri nets and reversal-bounded counter automata. Moreover, we improve both lower and upper bounds for language equivalence for exponent-sensitive commutative grammars.

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Christoph Haase, Piotr Hofman. 2015-06-25. Tightening the Complexity of Equivalence Problems for Commutative Grammars. https://arxiv.org/abs/1506.07774

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