This paper is devoted to Wiener index of directed graphs, more precisely grids. The grid Gm, n the Cartesian product Pm□Pn paths on m and vertices, in a particular case when = 2, it called ladder graph Ln. Kraner Šumenjak et al. 2021 proved that maximum digraph, which obtained by orienting edges Ln, all layers isomorphic one factor are same way except (corresponding an endvertex other factor) p...

The Wiener index of a network, introduced by the chemist Harry [30], is sum distances between all pairs nodes in network. This index, originally used chemical graph representations non-hydrogen atoms molecule, considered to be fundamental and useful network descriptor. We study problem constructing geometric networks on point sets Euclidean space that minimize index: given set P n points $$\mat...