New worst upper bound for #SAT
نویسندگان
چکیده
The rigorous theoretical analyses of algorithms for #SAT have been proposed in the literature. As we know, previous algorithms for solving #SAT have been analyzed only regarding the number of variables as the parameter. However, the time complexity for solving #SAT instances depends not only on the number of variables, but also on the number of clauses. Therefore, it is significant to exploit the time complexity from the other point of view, i.e. the number of clauses. In this paper, we present algorithms for solving #2-SAT and #3-SAT with rigorous complexity analyses using the number of clauses as the parameter. By analyzing the algorithms, we obtain the new worst-case upper bounds O(1.1892) for #2-SAT and O(1.4142) for #3-SAT, where m is the number of clauses.
منابع مشابه
New upper bound for the #3-SAT problem
We present a new deterministic algorithm for the #3-SAT problem, based on the DPLL strategy. It uses a new approach for counting models of instances with low density. This allows us to assume the adding of more 2-clauses than in previous algorithms. The algorithm achieves a running time of O(1.6423) in the worst case which improves the current best bound of O(1.6737) by Dahllöf et al.
متن کاملClause Shortening Combined with Pruning Yields a New Upper Bound for Deterministic SAT Algorithms
We give a deterministic algorithm for testing satisfiability of Boolean formulas in conjunctive normal form with no restriction on clause length. Its upper bound on the worst-case running time matches the best known upper bound for randomized satisfiability-testing algorithms [6]. In comparison with the randomized algorithm in [6], our deterministic algorithm is simpler and more intuitive.
متن کاملNew Worst-Case Upper Bound for #2-SAT and #3-SAT with the Number of Clauses as the Parameter
The rigorous theoretical analyses of algorithms for #SAT have been proposed in the literature. As we know, previous algorithms for solving #SAT have been analyzed only regarding the number of variables as the parameter. However, the time complexity for solving #SAT instances depends not only on the number of variables, but also on the number of clauses. Therefore, it is significant to exploit t...
متن کاملExact Max 2-Sat: Easier and Faster
Prior algorithms known for exactly solving Max 2-Sat improve upon the trivial upper bound only for very sparse instances. We present new algorithms for exactly solving (in fact, counting) weighted Max 2-Sat instances. One of them has a good performance if the underlying constraint graph has a small separator decomposition, another has a slightly improved worst case performance. For a 2-Sat inst...
متن کاملNew Methods for 3-SAT Decision and Worst-case Analysis
We prove the worst-case upper bound 1:5045 n for the time complexity of 3-SAT decision, where n is the number of variables in the input formula, introducing new methods for the analysis as well as new algorithmic techniques. We add new 2-and 3-clauses, called \blocked clauses", generalizing the extension rule of \Extended Resolution." Our methods for estimating the size of trees lead to a reene...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- CoRR
دوره abs/1006.1537 شماره
صفحات -
تاریخ انتشار 2010