<Dl> <Dd> A strongly connected simple directed graph with n vertices is Hamiltonian if every vertex has a full degree greater than or equal to n . </Dd> </Dl> <Dd> A strongly connected simple directed graph with n vertices is Hamiltonian if every vertex has a full degree greater than or equal to n . </Dd> <P> Meyniel (1973) </P> <Dl> <Dd> A strongly connected simple directed graph with n vertices is Hamiltonian if the sum of full degrees of every pair of distinct non-adjacent vertices is greater than or equal to 2n − 1 . </Dd> </Dl>

When does a graph have a hamiltonian circuit