3-Coloring in Time O(1.3289^n)
نویسندگان
چکیده
We consider worst case time bounds for NP-complete problems including 3-SAT, 3-coloring, 3-edge-coloring, and 3-list-coloring. Our algorithms are based on a constraint satisfaction (CSP) formulation of these problems. 3-SAT is equivalent to (2, 3)-CSP while the other problems above are special cases of (3, 2)-CSP; there is also a natural duality transformation from (a, b)-CSP to (b, a)-CSP. We give a fast algorithm for (3, 2)-CSP and use it to improve the time bounds for solving the other problems listed above. Our techniques involve a mixture of Davis-Putnam-style backtracking with more sophisticated matching and network flow based ideas.
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عنوان ژورنال:
- J. Algorithms
دوره 54 شماره
صفحات -
تاریخ انتشار 2005