# Mihály Hujter

• Discrete Mathematics
• 1992
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)? This question was motivated by practical problems in scheduling and VLSI theory. Here we investigate its complexity status(More)
• 1993
We continue the study of the following general problem on vertex col-orings 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 graph classes which(More)
• Combinatorics, Probability & Computing
• 1996
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(More)
• Networks
• 1993
For a natural number t , denote by N, the graph K2,\tK2, i.e. the graph obtained by deleting a perfect matching from the complete graph of order 2t. For example, NI is the edgeless graph on 2 vertices, N2 is the 4-cycle, and N3 is the octahedron graph shown in Fig. 1. The graphs N, were first studied by Neumann in 1942 (see [2, 61). We say that a graph G =(More)
• Math. Meth. of OR
• 1999
In this note we investigate the computational complexity of the transportation problem with a permutable demand vector, TP-PD for short. In the TP-PD, the goal is to permute the elements of the given integer demand vector b  b1; . . . ; bn in order to minimize the overall transportation costs. Meusel and Burkard [6] recently proved that the TP-PD is(More)
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 graph classes which(More)