Ranking Tournaments
نویسنده
چکیده
A tournament is an oriented complete graph. The feedback arc set problem for tournaments is the optimization problem of determining the minimum possible number of edges of a given input tournament T whose reversal makes T acyclic. Ailon, Charikar and Newman showed that this problem is NP-hard under randomized reductions. Here we show that it is in fact NP-hard. This settles a conjecture of Bang-Jensen and Thomassen.
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عنوان ژورنال:
- SIAM J. Discrete Math.
دوره 20 شماره
صفحات -
تاریخ انتشار 2006