A note on parity constrained orientations
نویسندگان
چکیده
This note extends the results of Frank, Jordán, and Szigeti [1] on parity constrained orientations with connectivity requirements. Given a hypergraph H, a non-negative intersecting supermodular set function p, and a preferred in-degree parity for every node, a formula is given on the minimum number of nodes with wrong in-degree parity in an orientation of H covering p. It is shown that the minimum number of nodes with wrong in-degree parity in a strongly connected orientation cannot be characterized by a similar formula.
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ورودعنوان ژورنال:
- Combinatorica
دوره 29 شماره
صفحات -
تاریخ انتشار 2009