Weighted Parameters in (P5, P5)-free Graphs

Abstract We use the modular decomposition to give O(n(m + n) algorithms for finding a maximum weighted clique (respectively stable set) and an approximate weighted colouring (respectively partition into cliques) in a (P 5 , P 5 )- free graph. As a by-product, we obtain an O(m + n) algorithm for finding a minimum weighted transversal of the C5 in a (P 5 , P 5 )- free graph.