Backbone solving algorithm based on heuristic thinking

In 1997, the definition of the backbone was proposed for the first time -- It was a set of variables that with invariant assignments in the solution of SAT problems. The scale of the backbone was closely related to the scale of the search in the SAT(Boolean Satisfiability Problem) problem, while it had important applications in fault diagnosis, stochastic 3-SAT problem and verification of the quality implication term, so that it was very important to solve the backbone at high speed. In 2010, J. Marques-Silva proposed one test per time algorithm, which greatly improved the computing efficiency of backbone. Based on the one test per time, this paper drew on the heuristic thinking, which designed the scoring mechanism and filtering strategy, also it had adjust the set to be tested. Based on this idea, this paper proposed the heuristic backbone algorithm, which could improve the speed of backbone solution. The test sample had used the benchmark standard test sample and the 2017 SAT competition test sample. The experimental results showed that compared with the one test per time algorithm, the solving time of the heuristic backbone algorithm had been significantly improved.