2 Metric Traveling Salesman
نویسندگان
چکیده
The traveling salesman problem is a classical NP-hard problem, and also hard to approximate at all under the assumption P 6= NP. Definition 1. A vertex tour of a graph G is a path which visits all vertices and returns to its starting vertex. This is another name for a Hamiltonian cycle on G. Traveling salesman problems involve finding a tour of undirected graph G with edge weights d(·), which we can think of as a sequence of vertices π = (v1, v2, . . .). The cost of a tour is the sum of costs of edges it traverses.
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