Author(s)

Bing Zhou

Department of Mathematics, Trent University, Peterborough, ON K9J 7B8, Canada.

We say that a parameter p of directed graphs has the interval property if for every graph G and orientations of G, p can take every value between its minimum and maximum values. Let λ be the length of the longest directed path. A question asked by C. Lin in [1] is equivalent to the question of whether λ has the interval property. In this note, we answer this question in the affirmative. We also show that the diameter of directed graphs does not have the interval property.

Directed Graphs, Graph Orientation, Interval Property, Longest Path, Path Length, Diameter

Zhou, B. (2017) Length of the Longest Path and Diameter in Orientations of Graphs. Open Journal of Discrete Mathematics, 7, 65-70. doi: 10.4236/ojdm.2017.72007.