Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Copyless Cost-Register Automata: Structure, Expressiveness, and Closure
  Properties   Cost register automata (CRA) and its subclass, copyless CRA, were recently
proposed by Alur et al. as a new model for computing functions over strings. We
study some structural properties, expressiveness, and closure properties of
copyless CRA. We show that copyless CRA are strictly less expressive than
weighted automata and are not closed under reverse operation. To find a better
class we impose restrictions on copyless CRA, which ends successfully with a
new robust computational model that is closed under reverse and other
extensions.

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The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
5
The categories of this paper are: gr-qc
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The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
4
The categories of this paper are: cond-mat
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: math-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: acc-phys
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The categories of this paper are: stat
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The categories of this paper are: q-fin
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The categories of this paper are: bayes-an