Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Parity to Safety in Polynomial Time for Pushdown and Collapsible
  Pushdown Systems   We give a direct polynomial-time reduction from parity games played over the
configuration graphs of collapsible pushdown systems to safety games played
over the same class of graphs. That a polynomial-time reduction would exist was
known since both problems are complete for the same complexity class. Coming up
with a direct reduction, however, has been an open problem. Our solution to the
puzzle brings together a number of techniques for pushdown games and adds three
new ones. This work contributes to a recent trend of liveness to safety
reductions which allow the advanced state-of-the-art in safety checking to be
used for more expressive specifications.

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The categories of this paper are: hep-ph
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
22
The categories of this paper are: chao-dyn
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The categories of this paper are: math
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The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
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The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
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The categories of this paper are: gr-qc