Precoloring Extension 3: Classes of Perfect Graphs
نویسندگان
چکیده
We continue the study of the following general problem on vertex colorings of graphs. Suppose that some vertices of a graph G are assigned to some colors. Can this “precoloring” be extended to a proper coloring of G with at most k colors (for some given k)? Here we investigate the complexity status of precoloring extendibility on some classes of perfect graphs, giving good characterizations (necessary and sufficient conditions) that lead to algorithms with linear or polynomial running time. It is also shown how a larger subclass of perfect graphs can be derived from graphs containing no induced path on four vertices.
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عنوان ژورنال:
- Combinatorics, Probability & Computing
دوره 5 شماره
صفحات -
تاریخ انتشار 1996