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arXiv · 1002.3511

Range Reporting for Moving Points on a Grid

Marek Karpinski·J. Ian Munro·Yakov Nekrich
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Abstract

In this paper we describe a new data structure that supports orthogonal range reporting queries on a set of points that move along linear trajectories on a $U\times U$ grid. The assumption that points lie on a $U\times U$ grid enables us to significantly decrease the query time in comparison to the standard kinetic model. Our data structure answers queries in $O(\sqrt{\log U/\log \log U}+k)$ time, where $k$ denotes the number of points in the answer. The above improves over the $Ω(\log n)$ lower bound that is valid in the infinite-precision kinetic model. The methods used in this paper could be also of independent interest.

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Marek Karpinski, J. Ian Munro, Yakov Nekrich. 2010-02-18. Range Reporting for Moving Points on a Grid. https://arxiv.org/abs/1002.3511

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