Cops and Robbers on Planar‐Directed Graphs
Cops and Robbers on Planar‐Directed Graphs
Abstract Aigner and Fromme initiated the systematic study of the cop number of a graph by proving the elegant and sharp result that in every connected planar graph, three cops are sufficient to win a natural pursuit game against a single robber. This game, introduced by Nowakowski and Winkler, is …