Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: New exact relations for steady irrotational two-dimensional gravity and
  capillary surface waves
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
6
The categories of this paper are: astro-ph
14
The categories of this paper are: math-ph
4
The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga
28
The categories of this paper are: alg-geom
20
The categories of this paper are: acc-phys
25
The categories of this paper are: patt-sol