Approximating k-outconnected Subgraph Problems
نویسندگان
چکیده
We present approximation algorithms and structural results for problems in network design. We give improved approximation algorithms for nding min-cost k-outconnected graphs with either a single root or multiple roots for (i) uniform costs, and (ii) metric costs. The improvements are obtained by focusing on single-root k-outconnected graphs and proving (i) a version of Mader's critical cycle theorem and (ii) an extension of a splitting oo theorem by Bienstock et al.
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