Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Ab initio study of ferromagnetism induced by magnetic impurities in
  rutile TiO2
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg