Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: A Linear-Time Algorithm for Minimum $k$-Hop Dominating Set of a Cactus
  Graph
25
The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
21
The categories of this paper are: adap-org
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess