Backdoors to q-Horn

3 years 24 days ago
Backdoors to q-Horn
The class q-Horn, introduced by Boros, Crama and Hammer in 1990, is one of the largest known classes of propositional CNF formulas for which satisfiability can be decided in polynomial time. This class properly contains the fundamental classes of Horn and Krom formulas as well as the class of renamable (or disguised) Horn formulas. In this paper we extend this class so that its favorable algorithmic properties can be made accessible to formulas that are outside but “close” to this class. We show that deciding satisfiability is fixed-parameter tractable parameterized by the distance of the given formula from q-Horn. The distance is measured by the smallest number of variables that we need to delete from the formula in order to get a q-Horn formula, i.e., the size of a smallest deletion backdoor set into the class q-Horn. This result generalizes known fixedparameter tractability results for satisfiability decision with respect to the parameters distance from Horn, Krom, and ren...
Serge Gaspers, Sebastian Ordyniak, M. S. Ramanujan
Added 29 Mar 2016
Updated 29 Mar 2016
Type Journal
Year 2016
Authors Serge Gaspers, Sebastian Ordyniak, M. S. Ramanujan, Saket Saurabh, Stefan Szeider
Comments (0)