Online Coloring of Comparability Graphs: some results
نویسندگان
چکیده
We study online partitioning of posets from a graph theoretical point of view, which is coloring and cocoloring in comparability graphs. For the coloring problem, we analyse the First-Fit algorithm and show a ratio of O( √ n); furthermore, we devise an algorithm with a competitivity ratio of χ+1 2 . For the cocoloring problem, we point out a tight bound of n 4 + 1 2 and we give better bounds in some more restricted cocoloring problems.
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تاریخ انتشار 2007