# Why Some Heaps Support Constant-Amortized-Time Decrease-Key Operations, and Others Do Not

@article{Iacono2014WhySH,
title={Why Some Heaps Support Constant-Amortized-Time Decrease-Key Operations, and Others Do Not},
author={John Iacono and {\"O}zg{\"u}r {\"O}zkan},
journal={ArXiv},
year={2014},
volume={abs/1302.6641}
}
• Published 26 February 2013
• Computer Science
• ArXiv
A lower bound is presented which shows that a class of heap algorithms in the pointer model with only heap pointers must spend $$\Omega \left( \frac{\log \log n}{\log \log \log n} \right)$$ amortized time on the Decrease-Key operation (given O(logn) amortized-time Extract-Min). Intuitively, this bound shows the key to having O(1)-time Decrease-Key is the ability to sort O(logn) items in O(logn) time; Fibonacci heaps [M. .L. Fredman and R. E. Tarjan. J. ACM 34(3):596-615 (1987)] do this through…
A Tight Lower Bound for Decrease-Key in the Pure Heap Model
• Computer Science
ArXiv
• 2014
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• Computer Science
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D S ] 2 2 O ct 2 01 5 Hollow Heaps ∗
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• Computer Science
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• 2018
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• Mathematics, Computer Science
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• 2016
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