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A Simple Mergeable Dictionary

Author Adam Karczmarz

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Adam Karczmarz

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Adam Karczmarz. A Simple Mergeable Dictionary. In 15th Scandinavian Symposium and Workshops on Algorithm Theory (SWAT 2016). Leibniz International Proceedings in Informatics (LIPIcs), Volume 53, pp. 7:1-7:13, Schloss Dagstuhl - Leibniz-Zentrum für Informatik (2016)


A mergeable dictionary is a data structure storing a dynamic subset S of a totally ordered set U and supporting predecessor searches in S. Apart from insertions and deletions to S, we can both merge two arbitrarily interleaved dictionaries and split a given dictionary around some pivot x. We present an implementation of a mergeable dictionary matching the optimal amortized logarithmic bounds of Iacono and Ökzan [Iacono/Ökzan,ICALP'10]. However, our solution is significantly simpler. The proposed data structure can also be generalized to the case when the universe U is dynamic or infinite, thus addressing one issue of [Iacono/Ökzan,ICALP'10].
  • dictionary
  • mergeable
  • data structure
  • merge
  • split


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