A short proof of the NP-completeness of minimum sum interval coloring
نویسنده
چکیده
In the minimum sum coloring problem we have to assign positive integers to the vertices of a graph in such a way that neighbors receive different numbers and the sum of the numbers is minimized. Szkalicki [9] has shown that minimum sum coloring is NP-hard for interval graphs. Here we present a simpler proof of this result.
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عنوان ژورنال:
- Oper. Res. Lett.
دوره 33 شماره
صفحات -
تاریخ انتشار 2005