Precoloring extension on unit interval graphs
نویسنده
چکیده
In the precoloring extension problem we are given a graph with some of the vertices having a preassigned color and it has to be decided whether this coloring can be extended to a proper k-coloring of the graph. Answering an open question of Hujter and Tuza [6], we show that the precoloring extension problem is NP-complete on unit interval graphs.
منابع مشابه
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 154 شماره
صفحات -
تاریخ انتشار 2006