CADICAL at the SAT Race 2019

Our SAT solver CADICAL provides a clean, documented, easy to understand and modify state-of-the-art solver, based on CDCL [1] with inprocessing [2]. Earlier versions participated in the SAT competition 2017 and 2018. Here we only describe differences to these versions [3], [4]. Even though CADICAL performed well on unsatisfiable instances in the SAT Competition 2018, the performance on satisfiable instances was behind the top solvers in that competition. Thus a large part of the changes made and described in this note are motivated by trying to improve CADICAL on satisfiable instances without loosing its good performance on unsatisfiable instances.

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