On the Implementation of Weight Constraint Rules in Conflict-Driven ASP Solvers

  • Martin Gebser
  • Roland Kaminski
  • Benjamin Kaufmann
  • Torsten Schaub
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5649)


We present the first comprehensive approach to integrating cardinality and weight rules into conflict-driven ASP solving. We begin with a uniform, constraint-based characterization of answer sets in terms of nogoods. This provides the semantic underpinnings of our approach in fixing all necessary inferences that must be supported by an appropriate implementation. We then provide key algorithms detailing the salient features needed for implementing weight constraint rules. This involves a sophisticated unfounded set checker as well as an extended propagation algorithm along with the underlying data structures. We implemented our techniques within the ASP solver clasp and demonstrate their effectiveness by an experimental evaluation.


Unit Propagation Normal Rule Cardinality Constraint Weight Constraint Weight Rule 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Martin Gebser
    • 1
  • Roland Kaminski
    • 1
  • Benjamin Kaufmann
    • 1
  • Torsten Schaub
    • 1
  1. 1.Institut für InformatikUniversität PotsdamPotsdam

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