The Probabilistic Analysis of a Greedy Satisfiability Algorithm
نویسندگان
چکیده
On input a random 3-CNF formula of clauses-to-variables ratio r3 applies repeatedly the following simple heuristic: Set to True a literal that appears in the maximum number of clauses, irrespective of their size and the number of occurrences of the negation of the literal (ties are broken randomly; 1-clauses when they appear get priority). We prove that for r3 < 3.42 this heuristic succeedswith probability asymptotically bounded away fromzero. Previously, heuristics of increasing sophistication were shown to succeed for r3 < 3.26. We improve up to r3 < 3.52 by further exploiting the degree of the negation of the evaluated toTrue literal. © 2005Wiley Periodicals, Inc. RandomStruct. Alg., 28, 444–480, 2006
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ورودعنوان ژورنال:
- Random Struct. Algorithms
دوره 28 شماره
صفحات -
تاریخ انتشار 2002