The Proper Interval Colored Graph Problem for Caterpillar Trees
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چکیده
This paper studies the computational complexity of the Proper interval colored graph problem (picg), when the input graph is a colored tree. We show that the problem is hard for the class of caterpillar trees. To prove our result we make use of a close relationship between intervalizing problems and graph layout problems. We deene a graph layout problem the Proper colored layout problem (pclp). Although the pclp is not equivalent to the picg, by transforming the input graph we will establish a close relationship between both problems. The main result is that the picg is NP-complete for colored caterpillars of hair length 2 and in P for caterpillars of hair length 1 or 0.
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تاریخ انتشار 2004