The third open Answer Set Programming competition
  Answer Set Programming (ASP) is a well-established paradigm of declarative
programming in close relationship with other declarative formalisms such as SAT
Modulo Theories, Constraint Handling Rules, FO(.), PDDL and many others. Since
its first informal editions, ASP systems have been compared in the now
well-established ASP Competition. The Third (Open) ASP Competition, as the
sequel to the ASP Competitions Series held at the University of Potsdam in
Germany (2006-2007) and at the University of Leuven in Belgium in 2009, took
place at the University of Calabria (Italy) in the first half of 2011.
Participants competed on a pre-selected collection of benchmark problems, taken
from a variety of domains as well as real world applications. The Competition
ran on two tracks: the Model and Solve (M&S) Track, based on an open problem
encoding, and open language, and open to any kind of system based on a
declarative specification paradigm; and the System Track, run on the basis of
fixed, public problem encodings, written in a standard ASP language. This paper
discusses the format of the Competition and the rationale behind it, then
reports the results for both tracks. Comparison with the second ASP competition
and state-of-the-art solutions for some of the benchmark domains is eventually
discussed.
  To appear in Theory and Practice of Logic Programming (TPLP).
