Any graph problem, which is NP-hard in general graphs, becomes polynomial-time solvable when restricted to graphs in special classes. When does a difficult problem become easy? To answer thisâ€¦ (More)

In this paper we propose a structural characterization for a class of bipartite graphs defined by two forbidden induced subgraphs. We show that the obtained characterization leads to polynomial-timeâ€¦ (More)

The dissociation number of a graph G is the number of vertices in a maximum size induced subgraph of G with vertex degree at most 1. The problem of nding the dissociation number has been introducedâ€¦ (More)

We study the problem of finding optimal paths in network games with p players. Some polynomial-time algorithms for finding optimal paths and optimal by Nash strategies of the players in network gamesâ€¦ (More)