  In the graph balancing problem the goal is to orient a weighted undirected
graph to minimize the maximum weighted in-degree. This special case of makespan
minimization is NP-hard to approximate to a factor better than 3/2 even when
there are only two types of edge weights. In this note we describe a simple 3/2
approximation for the graph balancing problem with two-edge types, settling
this very special case of makespan minimization.
