Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Calculating a backtracking algorithm: an exercise in monadic program
  derivation
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess