Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: DMap: A Distributed Blockchain-based Framework for Online Mapping in
  Smart City
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
17
The categories of this paper are: q-fin