Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: ALPGEN, a generator for hard multiparton processes in hadronic
  collisions
2
The categories of this paper are: math
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics