Long cycles in subgraphs of (pseudo)random directed graphs
نویسندگان
چکیده
We study the resilience of random and pseudorandom directed graphs with respect to the property of having long directed cycles. For every 0 < γ < 1/2 we find a constant c = c(γ) such that the following holds. Let G = (V,E) be a (pseudo)random directed graph on n vertices and with at least a linear number of edges, and let G′ be a subgraph of G with (1/2 + γ)|E| edges. Then G′ contains a directed cycle of length at least (c − o(1))n. Moreover, there is a subgraph G′′ of G with (1/2 + γ − o(1))|E| edges that does not contain a cycle of length at least cn.
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عنوان ژورنال:
- Journal of Graph Theory
دوره 70 شماره
صفحات -
تاریخ انتشار 2012