Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: An incompressible Eulerian method for fluid-structure interaction with
  mixed soft and rigid solids
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
21
The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs