Technical Note - An Effective Heuristic for the M-Tour Traveling Salesman Problem with Some Side Conditions

This note presents a heuristic for determining very good solutions for the symmetric M-tour traveling salesman problem with some side conditions. These side conditions' pertain to load, distance and time, or sequencing restrictions. The heuristic is an extension of the highly successful one of Lin and Kernighan for the single traveling salesman problem. Computational experience with widely tested vehicle dispatch problems indicates that the proposed heuristic consistently yields better solutions than existing heuristics that have appeared in the literature. Run times grow approximately as N2.3, where N is the number of cities. The heuristic is generally slower than the modified SWEEP heuristic except on problems having a large number of points per route.