Disjoint paths in sparse graphs
نویسنده
چکیده
We generalize all the results obtained for maximum integer multiflow and minimum multicut problems in trees by Garg, Vazirani and Yannakakis [Primal-dual approximation algorithms for integral flow and multicut in trees, Algorithmica 18 (1997) 3–20] to graphs with a fixed cyclomatic number, while this cannot be achieved for other classical generalizations of trees. We also introduce the k-edge-outerplanar graphs, a class of planar graphs with arbitrary (but bounded) treewidth that generalizes the cacti, and show that the integrality gap of the maximum edge-disjoint paths problem is bounded in these graphs.
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 157 شماره
صفحات -
تاریخ انتشار 2009