论文标题
大约距离甲骨文遭受多个顶点故障
Approximate Distance Oracles Subject to Multiple Vertex Failures
论文作者
论文摘要
给定无向图$ g =(v,e)的$ n $顶点和$ m $边缘,重量为$ [1,w] $,我们构造了顶点敏感距离甲骨文(VSDO),它们是图形预处理的数据结构,并回答以下疑问:给出以下类型(近似值)$ u $和$ v $ in $ g-d $中的距离(即,删除$ d $中的顶点的图形$ g $)。 An oracle has stretch $α$ if it always holds that $δ_{G-D}(u,v)\le\tildeδ(u,v)\leα\cdotδ_{G-D}(u,v)$, where $δ_{G-D}(u,v)$ is the actual distance between $u$ and $v$ in $G-D$, and $\tildeδ(u,v)$ is the甲骨文报告的距离。 在本文中,我们为任何数字$ d $失败构建有效的VSDO。对于任何常量的$ c \ geq 1 $,我们提出了两个oracles: $ \ bullet $第一个甲骨文具有$ n^{2+1/c}(\ log n/ε)^{o(d)} \ cdot \ log w $,在$ {\ rm poly}(\ rm poly}(\ log n,d^c,d^c,d^c,log w w w w wog)中回答查询,\ log w w w w w w w log \ log \ log \ log w,ε^,ε^{ - ε^{-1 $ 1 $ 1 $ 1 $ 1+1++三. $ \ bullet $第二Oracle的大小$ n^{2+1/c} {\ rm poly}(\ log(nw),d)$,在$ {\ rm poly}中回答查询(\ rm poly}(\ log n,d^c,d^c,\ log \ log \ log \ log \ log \ log \ log w)$ time,并具有stretch $ {\ rm poly}(\ rm poly}(\ rm poly}(\ rm poly} $ n,d)$ n,d)$ n,d)。 这两个口腔都可以在其空间复杂性中进行多项式进行预处理。这些结果是对于任何恒定数量的顶点故障,通常在无向图中的任何恒定数量的顶点故障时,多形载体查询时间的第一个大约距离甲骨文。以前有$(1+ε)$ - 大约$ d $ - 边缘敏感距离甲骨文[Chechik等。 [2017]回答距离查询时,当$ d $ edges失败时,它们的大小$ o(n^2(\ log n/ε)^d \ cdot d \ log w)$和查询时间$ {\ rm poly}(\ log n,d,d,d,\ log log \ log \ log \ log \ w)$。
Given an undirected graph $G=(V,E)$ of $n$ vertices and $m$ edges with weights in $[1,W]$, we construct vertex sensitive distance oracles (VSDO), which are data structures that preprocess the graph, and answer the following kind of queries: Given a source vertex $u$, a target vertex $v$, and a batch of $d$ failed vertices $D$, output (an approximation of) the distance between $u$ and $v$ in $G-D$ (that is, the graph $G$ with vertices in $D$ removed). An oracle has stretch $α$ if it always holds that $δ_{G-D}(u,v)\le\tildeδ(u,v)\leα\cdotδ_{G-D}(u,v)$, where $δ_{G-D}(u,v)$ is the actual distance between $u$ and $v$ in $G-D$, and $\tildeδ(u,v)$ is the distance reported by the oracle. In this paper we construct efficient VSDOs for any number $d$ of failures. For any constant $c\geq 1$, we propose two oracles: $\bullet$ The first oracle has size $n^{2+1/c}(\log n/ε)^{O(d)}\cdot \log W$, answers a query in ${\rm poly}(\log n,d^c,\log\log W,ε^{-1})$ time, and has stretch $1+ε$, for any constant $ε>0$. $\bullet$ The second oracle has size $n^{2+1/c}{\rm poly}(\log (nW),d)$, answers a query in ${\rm poly}(\log n,d^c,\log\log W)$ time, and has stretch ${\rm poly}(\log n,d)$. Both of these oracles can be preprocessed in time polynomial in their space complexity. These results are the first approximate distance oracles of poly-logarithmic query time for any constant number of vertex failures in general undirected graphs. Previously there are $(1+ε)$-approximate $d$-edge sensitive distance oracles [Chechik et al. 2017] answering distance queries when $d$ edges fail, which have size $O(n^2(\log n/ε)^d\cdot d\log W)$ and query time ${\rm poly}(\log n, d, \log\log W)$.