A clique in a graph G is a complete subgraph of G. A clique covering (partition) of G is a collection C of cliques such that each edge of G occurs in at least (exactly) one clique...
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 intersectio...
Let S be a set of r red points and b = r +2 blue points in general position in the plane. A line determined by them is said to be balanced if in each open half-plane bounded by th...
We introduce a new measure for planar point sets S that captures a combinatorial distance that S is from being a convex set: The reflexivity (S) of S is given by the smallest numb...
We consider the problem of finding a sparse set of edges containing the minimum spanning tree (MST) of a random subgraph of G with high probability. The two random models that we ...