2-subcoloring is NP-complete for planar comparability graphs
نویسنده
چکیده
A k-subcoloring of a graph is a partition of the vertex set into at most k cluster graphs, that is, graphs with no induced P3. 2-subcoloring is known to be NP-complete for comparability graphs and three subclasses of planar graphs, namely triangle-free planar graphs with maximum degree 4, planar perfect graphs with maximum degree 4, and planar graphs with girth 5. We show that 2-subcoloring is also NP-complete for planar comparability graphs with maximum degree 4.
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ورودعنوان ژورنال:
- Inf. Process. Lett.
دوره 128 شماره
صفحات -
تاریخ انتشار 2017