Solving MAX-XOR-SAT Problems with Stochastic Local Search
نویسنده
چکیده
The MAX-SAT problem is to find a truth assignment that satisfies the maximum number of clauses in a finite set of logical clauses. In the special case of MAX-XOR-SAT, arising from Linear Cryptanalysis, each clause is a set of literals joined by exclusive-or (xor). Solving MAX-XOR-SAT is useful in finding keys to decrypt intercepted encrypted messages. This report presents and evaluates Xor-WalkSAT, a method for solving MAX-XOR-SAT. Xor-WalkSAT is a modification to the WalkSAT stochastic local search procedure, which was developed to solve SAT problems formulated in conjunctive normal form. Two alternatives are also presented: an algebraic method for solving XOR-SAT, where all the clauses are satisfiable, and a tranlation method, where the MAX-XOR-SAT problem is translated into conjunctive normal form and solved by WalkSAT.
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