A Faster Exact Algorithm for the Directed Maximum Leaf Spanning Tree Problem
نویسندگان
چکیده
Given a directed graph G = (V, A), the Directed Maximum Leaf Spanning Tree problem asks to compute a directed spanning tree (i.e., an out-branching) with as many leaves as possible. By designing a Branch-and-Reduced algorithm combined with the Measure&Conquer technique for running time analysis, we show that the problem can be solved in time O(1.9043) using polynomial space. Hitherto, there have been only few examples. Provided exponential space this run time upper bound can be lowered to O(1.8139).
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