Extremal digraphs on Meyniel-type condition for hamiltonian cycles in balanced bipartite digraphs

Ruixia Wang, Linxin Wu, Wei Meng

Let $D$ be a strong balanced digraph on $2a$ vertices. Adamus et al. have proved that $D$ is hamiltonian if $d(u)+d(v)\ge 3a$ whenever $uv\notin A(D)$ and $vu\notin A(D)$. The lowe…