An optimal rounding for half-integral weighted minimum strongly connected spanning subgraph

نویسندگان

چکیده

• We give a 1.5-approximation for half-integral weighted MSCSS. Our matches known integrality gap lower bound. 2 − f approximation if LP values are bounded below by . In the minimum strongly connected spanning subgraph ( WMSCSS ) problem we must purchase minimum-cost of digraph. show that linear program (LP) solutions can be efficiently rounded to integral at multiplicative 1.5 cost. This rounding bound instance. More generally, whose non-zero entries least value > 0 cost

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ژورنال

عنوان ژورنال: Information Processing Letters

سال: 2021

ISSN: ['1872-6119', '0020-0190']

DOI: https://doi.org/10.1016/j.ipl.2020.106067