Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Limits on contact interactions and leptoquarks at HERA
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ