Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: No Far-Infrared-Spectroscopic Gap in Clean and Dirty High-T$_C$
  Superconductors
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
3
The categories of this paper are: physics
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
2
The categories of this paper are: math
9
The categories of this paper are: nlin
6
The categories of this paper are: astro-ph