Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: First-principles study of electronic structures and optical properties
  of Cu, Ag, and Au-doped anatase TiO2
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin