Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Rainbow C_4's and Directed C_4's: the Bipartite Case Study   In this paper we obtain a new sufficient condition for the existence of
directed cycles of length 4 in oriented bipartite graphs. As a corollary, a
conjecture of H. Li is confirmed. As an application, a sufficient condition for
the existence of rainbow cycles of length 4 in bipartite edge-colored graphs is
obtained.

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The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
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The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
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The categories of this paper are: solv-int
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The categories of this paper are: mtrl-th
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The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: dg-ga
1
The categories of this paper are: cs