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arXiv · 1104.3045

Confluent Persistence Revisited

Abstract

It is shown how to enhance any data structure in the pointer model to make it confluently persistent, with efficient query and update times and limited space overhead. Updates are performed in $O(\log n)$ amortized time, and following a pointer takes $O(\log c \log n)$ time where $c$ is the in-degree of a node in the data structure. In particular, this proves that confluent persistence can be achieved at a logarithmic cost in the bounded in-degree model used widely in previous work. This is a $O(n/\log n)$-factor improvement over the previous known transform to make a data structure confluently persistent.

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Sebastien Collette, John Iacono, Stefan Langerman. 2011-04-15. Confluent Persistence Revisited. https://arxiv.org/abs/1104.3045

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