Improved Approximations for TSP with Simple Precedence Constraints

In this paper, we consider variants of the traveling salesman problem with precedence constraints. We characterize hard input instances for Christofides' algorithm and Hoogeveen's algorithm by relating the two underlying problems, i. e., the traveling salesman problem and the problem of finding a minimum-weight Hamiltonian path between two prespecified vertices. We show that the sets of metric worst-case instances for both algorithms are disjoint in the following sense. There is an algorithm that, for any input instance, either finds a Hamiltonian tour that is significantly bet

• Type: Conference
• Year: 2010
• Where: CIAC
• Authors: Hans-Joachim Boeckenhauer, Ralf Klasing, Tobias Moemke, Monika Steinová
• Keywords: Algorithms, CIAC 2010, Hard Input Instances, Input Instance, Traveling Salesman Problem