Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Efficient Algorithms for Optimal Control of Quantum Dynamics: The
  "Krotov'' Method unencumbered
20
The categories of this paper are: acc-phys
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
2
The categories of this paper are: math
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
19
The categories of this paper are: eess