Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: The use of the Morse theory to estimate the number of nontrivial
  solutions of a nonlinear Schr\"odinger equation with magnetic field
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
6
The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat
9
The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
18
The categories of this paper are: econ