Structural Parameterizations of the Mixed Chinese Postman Problem
نویسندگان
چکیده
In the Mixed Chinese Postman Problem (MCPP), given a weighted mixed graph G (G may have both edges and arcs), our aim is to find a minimum weight closed walk traversing each edge and arc at least once. The MCPP parameterized by the number of edges in G or the number of arcs in G is fixed-parameter tractable as proved by van Bevern et al. (in press) and Gutin, Jones and Sheng (ESA 2014), respectively. Solving an open question of van Bevern et al. (in press), we show that unexpectedly the MCPP parameterized by the treewidth of G is W[1]-hard. In fact, we prove that even the MCPP parameterized by the pathwidth of G is W[1]-hard.
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