Minimum sum set coloring of trees and line graphs of trees

BONOMO, FLAVIA; DURÁN, GUILLERMO; MARENCO, JAVIER; VALENCIA-PABON, MARIO

DISCRETE APPLIED MATHEMATICS

ELSEVIER SCIENCE BV

Año: 2011 vol. 159 p. 288 - 294

0166-218X

In this paper, we study the Minimum Sum Set Coloring (MSSC) problem which consists in assigning a set of x(v) positive integers to each vertex v of a graph so that the intersection of sets assigned to adjacent vertices be empty and the sum of the assigned set of numbers to each vertex of the graph is minimum. The MSSC problem occurs in two versions: non-preemptive and preemptive. We show that the MSSC problem is strongly NP-hard both in the preemptive case on trees and in the non-preemptive case in line graphs of trees. Finally, we give exact parameterized algorithms for these two versions on trees and line graphs of trees.