Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Planar Decompositions and the Crossing Number of Graphs with an Excluded
  Minor
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess