Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Hydra: A Multiple Blockchain Protocol for Improving Transaction
  Throughput
15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
6
The categories of this paper are: astro-ph