Backdoor is one of these structures

which can effectively improve the efficiency of the SAT problem solving

and which become a focus of study in recent years.The variable assignment for backdoors can reduce the search branch of SAT problem solving process effectively

thereby reducing the time complexity and space complexity of sat problem solver.In order to improve the efficiency of the SAT problem

this paper presents the improved algorithm of backdoor sets for sloving SAT problem

and provides the definition of the smallest backdoor sets.The heuristic is joined in this algorithm

so the smaller backdoor sets can be solved in this way

Finally

this paper proposed summary and outlook.