The x-and-y-axes travelling salesman problem forms a special case of the Euclidean TSP, where all cities are situated on the x-axis and on the y-axis of an orthogonal coordinate system of the Euclidean plane. By carefully analyzing the underlying combinatorial and geometric structures, we show...

We investigate a special case of the unbounded knapsack problem in which the item weights form an arithmetic sequence. We derive a polynomial time algorithm for this special case with running time O(n8), where n denotes the number of distinct items in the instance. Furthermore, we extend our...

The students of the Department of Industrial Design at the TU Eindhoven are allowed to design part of their curriculum by selecting courses from a huge course pool. They do this by handing in ordered preference lists with their favorite courses for the forthcoming time period. Based on this...