Approximation Algorithms and Hardness of the k-Route Cut Problem

  title={Approximation Algorithms and Hardness of the k-Route Cut Problem},
  author={Julia Chuzhoy and Yury Makarychev and Aravindan Vijayaraghavan and Yuan Zhou},
We study the <i>k</i>-route cut problem: given an undirected edge-weighted graph <i>G</i> = (<i>V</i>, <i>E</i>), a collection {(<i>s</i><sub>1</sub>, <i>t</i><sub>1</sub>), (<i>s</i><sub>2</sub>, <i>t</i><sub>2</sub>), …, (<i>s<sub>r</sub></i>, <i>t<sub>r</sub></i>)} of source-sink pairs, and an integer connectivity requirement <i>k</i>, the goal is to find a minimum-weight subset <i>E</i>′ of edges to remove, such that the connectivity of every pair (<i>s<sub>i</sub></i>, <i>t<sub>i</sub></i… 

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