In this paper, we consider variants of the traveling salesman problem with precedence constraints. We characterize hard input instances for Christofides' algorithm and Hoogeve...
We consider the asymmetric traveling salesperson problem with -parameterized triangle inequality for [1/2, 1). That means, the edge weights fulfill w(u, v)
In this paper we introduce a general strategy for approximating the solution to minimisation problems in random regular graphs. We describe how the approach can be applied to the m...
We introduce several generalizations of classical computer science problems obtained by replacing simpler objective functions with general submodular functions. The new problems i...
We study the partial vertex cover problem. Given a graph G = (V, E), a weight function w : V → R+ , and an integer s, our goal is to cover all but s edges, by picking a set of v...