Succinct Data Structures for Path Queries
نویسندگان
چکیده
Consider a tree T on n nodes, each having a weight drawn from [1..σ]. In this paper, we design succinct data structures to encode T using nH(WT ) + o(n lg σ) bits of space, such that we can support path counting queries in O( lg σ lg lgn + 1) time, path reporting queries in O((occ+1)( lg σ lg lgn +1)) time, and path median and path selection queries in O( lg σ lg lg σ ) time, where H(WT ) is the entropy of the multiset of the weights of the nodes in T . Our results not only improve the best known linear space data structures [15], but also match the lower bounds for these path queries [18, 19, 16] when σ = Ω(n/polylog(n)).
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