Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Charm Hadronic Decays From FOCUS: Lessons Learnt   The FOCUS photoproduction experiment took data in the ninenties and produced
a wealth of results in charm physics. Some of the studies were seminal for
contemporary experiments, and even paved the way for the technology of many
charm and beauty analysis tools.

4
The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg