Recognizing Structural Patterns on Graphs for the Efficient Computation of #2SAT
نویسندگان
چکیده
To count models for two conjunctive forms (#2SAT problem) is a classic #P problem. We determine different structural patterns on the underlying graph of a 2-CF F allowing the efficient computation of #2SAT(F ). We show that if the constrained graph of a formula is acyclic or the cycles on the graph can be arranged as independent and embedded cycles, then the number of models of F can be counted efficiently.
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