Graph Theoretical Characterization and Computation of Answer Sets

We give a graph theoretical characterization of answer sets of normal logic programs. We show that there is a one-to-one correspondence between answer sets and a special, non-standard graph coloring of so-called block graphs of logic programs. This leads us to an alternative implementation paradigm to compute answer sets, by computing non-standard graph colorings. Our approach is rule-based and not atom-based like most of the currently known methods. We present an implementation for computing answer sets which works on polynomial space.

• Type: Conference
• Year: 2001
• Where: IJCAI
• Authors: Thomas Linke
• Keywords: Answer Sets, IJCAI 2001, IJCAI 2007, Logic Programs, Non-standard Graph Colorings