ARBITRARY ORIENTATIONS OF HAMILTON CYCLES IN DIGRAPHS

Abstract. Let n be sufficiently large and suppose that G is a digraph on n vertices where every vertex has in- and outdegree at least n/2. We show that G contains every orientation of a Hamilton cycle except, possibly, the antidirected one. The antidirected case was settled by DeBiasio and Molla, where the threshold is n/2 + 1. Our result is best possible and improves on an approximate result by Häggkvist and Thomason. 1