The pathwidth of a graph G is the minimum clique number of H minus one, over all interval supergraphs H of G. We prove in this paper that the PATHWIDTH problem is NP-hard for parti...
A graph class is sandwich monotone if, for every pair of its graphs G1 = (V, E1) and G2 = (V, E2) with E1 ⊂ E2, there is an ordering e1, . . . , ek of the edges in E2 \ E1 such ...
Chordal graphs, also called triangulated graphs, are important in algorithmic graph theory. In this paper we generalise the definition of chordal graphs to the class of directed ...
We consider the problem of aligned coloring of interval and chordal graphs. These problems have substantial applications to register allocation in compilers and have recently been ...
A graph is chordal if it does not contain any induced cycle of size greater than three. An alternative characterization of chordal graphs is via a perfect elimination ordering, whi...