# A Randomized Concurrent Algorithm for Disjoint Set Union

@article{Jayanti2016ARC,
title={A Randomized Concurrent Algorithm for Disjoint Set Union},
author={Siddhartha V. Jayanti and Robert Endre Tarjan},
journal={Proceedings of the 2016 ACM Symposium on Principles of Distributed Computing},
year={2016}
}
• Published 25 July 2016
• Computer Science, Mathematics
• Proceedings of the 2016 ACM Symposium on Principles of Distributed Computing
Disjoint set union is a basic problem in data structures with a wide variety of applications. [] Key Result Finally, under our independence assumption our algorithm achieves speedup close to linear for applications in which all or most of the processes can be kept busy, thereby partially answering an open problem posed by them.
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This paper gives a wait-free implementation of an efficient algorithm for union-find and shows that the worst case performance of the algorithm can be improved by simulating a synchronized algorithm, or bysimulating a larger machine if the data structure requests support sufficient parallelism.
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New lower and upper bounds on the time per operation are proved to implement solutions to some familiar dynamic data structure problems including list representation, subset ranking, partial sums, and the set union problem.
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