Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Competing interactions in two dimensional Coulomb systems: Surface
  charge heterogeneities in co-assembled cationic-anionic incompatible mixtures
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
3
The categories of this paper are: physics
24
The categories of this paper are: dg-ga
20
The categories of this paper are: acc-phys