Constant factor approximation to the bounded genus instances of ATSP
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چکیده
The symmetric traveling salesman problem (STSP) is a special case of ATSP in which the cost function is symmetric (i.e. c(u, v) = c(v, u)). Christofides in 1976 [6] discovered a 3/2approximation algorithm for STSP. No better approximation algorithm has since been found for the general symmetric metric case. However, polynomial-time approximation schemes have been found when the distances are shortest paths in a planar graph [13, 1] or a bounded-genus graph [7].
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تاریخ انتشار 2009