Genetic coding for solving both the stacker crane problem and its k-variant

The stacker crane problem (SCP) is more constrained than the traveling salesman problem (TSP) since there is a set of priori ordered edge pairs on any feasible tour of an instance of the SCP. Thus the SCP has a considerably larger search space than the TSP, and seems to be less paid attention by researchers, although important and ubiquitous. An approach based on genetic algorithms which is considered to produces reasonable good results very quickly is developed for the SCP and then extended into its k-variant, the k-stacker crane problem (the k-SCP). The genome representation used in the approach is a variant of those known to be popular for the TSP. A number of random samples are examined to ensure the efficiency of modelling the SCP and the k-SCP in a nonbinary genetic code herein