{ "id": "2012.07325", "version": "v2", "published": "2020-12-14T08:20:24.000Z", "updated": "2022-06-05T13:31:07.000Z", "title": "Fair Integral Submodular Flows", "authors": [ "AndrĂ¡s Frank", "Kazuo Murota" ], "comment": "27 pages. arXiv admin note: text overlap with arXiv:1907.02673", "categories": [ "math.CO" ], "abstract": "Integer-valued elements of an integral submodular flow polyhedron $Q$ are investigated which are decreasingly minimal (dec-min) in the sense that their largest component is as small as possible, within this, the second largest component is as small as possible, and so on. As a main result, we prove that the set of dec-min integral elements of $Q$ is the set of integral elements of another integral submodular flow polyhedron arising from $Q$ by intersecting a face of $Q$ with a box. Based on this description, we develop a strongly polynomial algorithm for computing not only a dec-min integer-valued submodular flow but even a cheapest one with respect to a linear cost-function. A special case is the problem of finding a strongly connected (or $k$-edge-connected) orientation of a mixed graph whose in-degree vector is decreasingly minimal.", "revisions": [ { "version": "v2", "updated": "2022-06-05T13:31:07.000Z" } ], "analyses": { "subjects": [ "90C27", "68R10" ], "keywords": [ "fair integral submodular flows", "dec-min integral elements", "dec-min integer-valued submodular flow", "integral submodular flow polyhedron arising", "decreasingly minimal" ], "note": { "typesetting": "TeX", "pages": 27, "language": "en", "license": "arXiv", "status": "editable" } } }