Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Finding steady-state solutions for ODE systems of zero, first and
  homogeneous second-order chemical reactions is NP-hard
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
14
The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol