Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: A Fortran 90 Hartree-Fock program for one-dimensional periodic
  $\pi$-conjugated systems using Pariser-Parr-Pople model
28
The categories of this paper are: alg-geom
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
19
The categories of this paper are: eess