Here you find instance definitions and the best known solutions (to our knowledge) for the 200, 400, 600, 800, and 1000 customer instances of Gehring & Homberger's extended VRPTW benchmark. The version reported here has a hierarchical objective: 1) Minimize number of vehicles 2) Minimize total distance. Distance is Euclidean, and the value of travel time between two nodes is equal to the value of distance. Distance and time should be calculated with double precision, total distance results are rounded to two decimals in the tables below. Exact methods typically use a total distance objective only and use integral or low precision distance and time calculations. Hence, results are not directly comparable.
Published April 18, 2008