Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Italian Domination of Cartesian Products of Directed Cycles   An Italian dominating function on a (di)graph $G$ with vertex set $V(G)$ is a
function $f: V(G) \to \{0, 1, 2\}$ such that every vertex $v \in V(G)$ such
that $f(v) = 0$ has an (in)neighbour assigned 2 or two (in)neighbours assigned
1. We complete the investigation of the Italian domination numbers of Cartesian
products of directed cycles.

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The categories of this paper are: econ
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The categories of this paper are: math-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: astro-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: quant-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: comp-gas
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The categories of this paper are: funct-an
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-lat
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The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-th
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The categories of this paper are: physics