The classic string indexing problem is to preprocess a S into compact data structure that supports efficient pattern matching queries. Typical queries include existential (decide if the occurs in S), reporting (return all positions where occurs), and counting number of occurrences pattern). In this paper we consider variant indexing, goal compactly represent such given two patterns $$P_1$$ $$P_...

Abstract We consider arc colourings of oriented graphs such that for each vertex the colours all out-arcs incident with and in-arcs form intervals. prove existence a colouring is an NP-complete problem. give solution problem r -regular graphs, transitive tournaments, small maximum degree, order some other classes graphs. state conjecture graph there exists consecutive colourable orientation con...