Satis ability Problems
نویسندگان
چکیده
We investigate the complexity of satis ability problems that surprisingly to the best of our knowledge have not yet been considered in the literature CNF SAT which we also denote by SAT asks for an assignment for a given formula that satis es all of its clauses While SAT is NP complete what is the complexity of SAT where it is asked for an assignment that satis es an odd number of clauses We show that SAT can be solved by a randomized algorithm in polynomial time The result is extended to Th SAT where we have a threshold instead of an or at the input level MaxSAT which we also denote by Th SAT is a generalization of CNF SAT and hence NP complete What is the complexity of the analogous optimization version of DNF SAT an easy problem Th SAT We show that Th SAT is NP complete and the same holds for Th SAT where we have a parity instead of an and at the input level
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