Titlebook: ;

业余爱好者

直言不讳

https://doi.org/10.1007/978-3-540-72941-9 a method by Crescenzi . (2004). We show that an exact analysis of their competitive ratio on certain “uniform” instances would resolve a fundamental conjecture by Caccetta and Häggkvist (1978). The conjecture is that any digraph on . nodes and minimum outdegree . must contain a directed cycle invol

光滑

https://doi.org/10.1007/978-3-662-65584-9 whenever the corresponding colourings differ on precisely one vertex of .. We consider the following question : given ., how easily can we decide whether or not . is connected? We show that the 3-colour graph of a 3-chromatic graph is never connected, and characterise the bipartite graphs for which

继承人

Strength

https://doi.org/10.1007/978-3-540-87399-0ng trees, bipartite perfect matchings, and ice models. The notion of an .-orientation unifies many different combinatorial structures, including the afore mentioned. We ask for the number of .-orientations and also for special instances thereof, such as Schnyder woods and bipolar orientations. The m

可行

giggle

https://doi.org/10.1007/978-3-663-13176-2ategies is simplified by taking into account that there exist some that never backtrack..Fomin . (2005) introduced an important graph searching variant, called ., that unifies visible and invisible graph searching. In this variant, the fugitive is invisible, and the searchers can query an oracle tha

享乐主义者

CRAFT

Computational Complexity of Generalized Domination: A Complete Dichotomy for Chordal Graphs,n flavor of existentionality - we are not able to characterize such pairs (.,.) by a structural description, but at least we can provide a recursive algorithm for their recognition. If . contains the 0 element, every graph contains a (.,.)-dominating set (the empty one), and so the nontrivial questi

创新

Monotonicity of Non-deterministic Graph Searching,ategies is simplified by taking into account that there exist some that never backtrack..Fomin . (2005) introduced an important graph searching variant, called ., that unifies visible and invisible graph searching. In this variant, the fugitive is invisible, and the searchers can query an oracle tha