Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: A Coarea Formula for Smooth Contact Mappings of Carnot--Carath\'{e}odory
  Spaces
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci