Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Monotone 3-Sat-4 is NP-complete   Monotone 3-Sat-4 is a variant of the satisfiability problem for boolean
formulae in conjunctive normal form. In this variant, each clause contains
exactly three literals---either all or none of them are positive, i.e., no
clause contains both a positive and a negative literal---and every variable
appears at most four times in the formula. Moreover, every clause consists of
three distinct literals. We show that Monotone 3-Sat-4 is NP-complete.

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The categories of this paper are: astro-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: eess
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The categories of this paper are: cond-mat
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The categories of this paper are: cmp-lg
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The categories of this paper are: gr-qc
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The categories of this paper are: chem-ph
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The categories of this paper are: solv-int
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The categories of this paper are: dg-ga
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The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
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The categories of this paper are: atom-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: plasm-ph
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The categories of this paper are: stat
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The categories of this paper are: funct-an