Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Climate simulations of early Mars with estimated precipitation, runoff,
  and erosion rates
5
The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
4
The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg