European Master in Computational Logic Master Thesis Backdoors for SAT
نویسندگان
چکیده
The concept of backdoor was introduced to try to explain the good performances achieved on real world SAT instances by solvers. A backdoor is a set of variables that, once decided, makes the rest of the problem simple (i.e. polynomial-time). In this thesis we provide a comprehensive overview on the state of the art of backdoors for SAT. Moreover, we study the relation between backdoors and parameterized complexity. In order to do so, we consider the problem of finding a smallest strong Hornbackdoor and we study it by means of the parameterized version of Vertex Cover. We conclude by presenting some interesting results obtained when analysing strong Hornbackdoors in instances from different domains.
منابع مشابه
Backdoor Treewidth for SAT
A strong backdoor in a CNF formula is a set of variables such that each possible instantiation of these variables moves the formula into a tractable class. The algorithmic problem of finding a strong backdoor has been the subject of intensive study, mostly within the parameterized complexity framework. Results to date focused primarily on backdoors of small size. In this paper we propose a new ...
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Acknowledgements This two years Master has been for me a great experience and allowed me to learn a lot from both the courses at the Universities of Bolzano and Madrid and from the working experience at the OEG reserch group in Madrid. There are several people that helped me in these two years, both when studying forthe exams and during the development of this thesis, whose help has been invalu...
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