Improved Bounds on the List Decreasing Heuristic for the Vertex Cover Problem
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چکیده
The list decreasing heuristic for the vertex cover problem is an online vertex covering algorithm. An upper bound ∆ /2+3/2 had been proposed on the approximation ratio for it, and a graph had also been given to reach a lower bound of ∆ /2+1/2. In this paper, we refine the techniques of previous researchers, and construct a new type of graphs which can enhance the lower bound to ∆ /2+1 , and all the graphs can be categorized into a group. Then we proposed a modified algorithm to obtain a tighter bound and prove it with an example.
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تاریخ انتشار 2011