Randomized Rounding Algorithms for Symmetric TSP 12 - 3 12 . 2 Good Edges , Random Spanning Trees and T - join Polytope
نویسنده
چکیده
We defined the symmetric TSP in lecture 6. The best known approximation algorithm for STSP is the 3/2 approximation algorithm of Christofides. The algorithm is very easy to describe, first choose a minimum cost spanning tree and then add that minimum cost Eulerian augmentation to the tree, that is the minimum cost set of edges to make the tree Eulerian. An undirected graph is Eulerian when every vertex has even degree. Therefore, the minimum cost Eulerian augmentation of a given subgraph is the minimum cost matching on the odd degree vertices of that subgraph.
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