The complexity of determining the rainbow vertex-connection of graphs
arXiv:1101.3126
Abstract
A vertex-colored graph is {\it rainbow vertex-connected} if any two vertices are connected by a path whose internal vertices have distinct colors, which was introduced by Krivelevich and Yuster. The {\it rainbow vertex-connection} of a connected graph , denoted by , is the smallest number of colors that are needed in order to make rainbow vertex-connected. In this paper, we study the computational complexity of vertex-rainbow connection of graphs and prove that computing is NP-Hard. Moreover, we show that it is already NP-Complete to decide whether . We also prove that the following problem is NP-Complete: given a vertex-colored graph , check whether the given coloring makes rainbow vertex-connected.
7 pages