A maze routing method of combined unity and infinity expansion distances

A method for maze routing problems which combines unity and infinity distances into the wavefront expansion phase of a generic Lee´s algorithm is described. A unity distance wavefront is maintained at each step of the expansion to guarantee finding minimum-length paths, while an infinity distance labeling scheme is adapted to ensure that the labels can be used to determine a minimum-corner path among them. Since the originally proposed three sequential expansions are replaced by a single one, the routing time is significantly improved