Look-Ahead Value Ordering for Constraint Satisfaction Problems
نویسندگان
چکیده
Looking ahead during search is often useful when solving constraint satisfaction problems. Previous studies have shown that looking ahead helps by causing dead-ends to occur earlier in the search, and by providing information that is useful for dynamic variable ordering. In this paper, we show that another bene t of looking ahead is a useful domain value ordering heuristic, which we call look-ahead value ordering or LVO. LVO counts the number of times each value of the current variable con icts with some value of a future variable, and the value with the lowest number of con icts is chosen rst. Our experiments show that look-ahead value ordering can be of substantial bene t, especially on hard constraint satisfaction problems.
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