On the Minimum Dummy - Arc Problem
نویسندگان
چکیده
A precedence relation can be represented non-uniquely by an activity on arc (AoA) directed acyclic graph (dag). This paper deals with the NP-hard problem of constructing an AoA dag having the minimum number o f arcs among those that have the minimum number of nodes. We show how this problem can be reduced in polynomial time to the set-cover problem so that the known methods of solving the set-cover problem can be applied. Several special cases that lead to easy set-cover problems are discussed.
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