Nearly Linear-Work Algorithms for Mixed Packing/Covering and Facility-Location Linear Programs
نویسنده
چکیده
We describe nearly linear-time approximation algorithms for explicitly given mixed packing/covering and facility-location linear programs. The algorithms compute (1+ǫ)-approximate solutions in time O(N log(N)/ǫ), where N is the number of non-zeros in the constraint matrix. We also describe parallel variants taking time O(polylog /ǫ) and requiring only near-linear total work, O(N polylog /ǫ). These are the first approximation schemes for these problems that have near-linear-time sequential implementations or near-linear-work polylog-time parallel implementations.
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