Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: On the optimality of Periodic barrier strategies for a spectrally
  positive L\'evy process
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
15
The categories of this paper are: nucl-ex