Inclusion of Unambiguous RE#s is NP-Hard

Pekka Kilpeläinen

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arXiv · 1111.0422

Inclusion of Unambiguous RE#s is NP-Hard

Pekka Kilpeläinen

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Abstract

We show that testing inclusion between languages represented by regular expressions with numerical occurrence indicators (RE#s) is NP-hard, even if the expressions satisfy the requirement of "unambiguity", which is required for XML Schema content model expressions.

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Pekka Kilpeläinen. 2011-11-02. Inclusion of Unambiguous RE#s is NP-Hard. https://arxiv.org/abs/1111.0422

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