A constant-factor approximation algorithm for the asymmetric traveling salesman problem

@article{Svensson2018ACA,
  title={A constant-factor approximation algorithm for the asymmetric traveling salesman problem},
  author={Ola Svensson and Jakub Tarnawski and L{\'a}szl{\'o} A. V{\'e}gh},
  journal={Proceedings of the 50th Annual ACM SIGACT Symposium on Theory of Computing},
  year={2018}
}
We give a constant-factor approximation algorithm for the asymmetric traveling salesman problem. Our approximation guarantee is analyzed with respect to the standard LP relaxation, and thus our result confirms the conjectured constant integrality gap of that relaxation. Our techniques build upon the constant-factor approximation algorithm for the special case of node-weighted metrics. Specifically, we give a generic reduction to structured instances that resemble but are more general than those… 
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A Constant-factor Approximation Algorithm for the Asymmetric Traveling Salesman Problem
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A constant-factor approximation algorithm for the asymmetric traveling salesman problem (ATSP) is given, showing that any algorithm for Subtour Partition Cover can be turned into an algorithm for ATSP while only losing a small constant factor in the performance guarantee.
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