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arXiv 0812.2775cs.DS
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距离最小化的最佳简洁性

Optimal Succinctness for Range Minimum Queries

Johannes Fischer

摘要:

对于n个有序对象的静态数组A,范围最小值查询要求两个指定数组索引之间的最小值的位置。我们展示了如何预处理A到一个计划的大小为2n+o(n)位,允许回答范围最小查询A在恒定的时间。在预处理步骤之后不允许访问A的重要设置中,该空间是渐近最优的。我们的方案可以在线性时间内计算,在构造时仅使用n + o(n)个附加位。有趣的副产品是,我们还改进了BPS或DFUDS编码树中的LCA计算。

英文摘要:

For a static array A of n ordered objects, a range minimum query asks for the position of the minimum between two specified array indices. We show how to preprocess A into a scheme of size 2n+o(n) bits that allows to answer range minimum queries on A in constant time. This space is asymptotically optimal in the important setting where access to A is not permitted after the preprocessing step. Our scheme can be computed in linear time, using only n + o(n) additional bits at construction time. In interesting by-product is that we also improve on LCA-computation in BPS- or DFUDS-encoded trees.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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