First-Fit is Linear on Posets Excluding Two Long Incomparable Chains
نویسندگان
چکیده
A poset is (r+s)-free if it does not contain two incomparable chains of size r and s, respectively. We prove that when r and s are at least 2, the First-Fit algorithm partitions every (r + s)-free poset P into at most 8(r− 1)(s− 1)w chains, where w is the width of P . This solves an open problem of Bosek, Krawczyk, and Szczypka (SIAM J. Discrete Math., 23(4):1992–1999, 2010).
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ورودعنوان ژورنال:
- Order
دوره 28 شماره
صفحات -
تاریخ انتشار 2011