Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: The moduli spaces of sheaves on K3 surfaces are irreducible symplectic
  varieties
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ