Abstract
Henriksen's algorithm is a priority queue implementation that has been proposed for the event list found in discrete event simulations. It offers several practical advantages over heaps and tree structures.
Although individual insertions ofO(n) complexity can easily be demonstrated to exist, the “self-adjusting” nature of the data structure seems to ensure that these will be rare. For this reason, a better measure of total running time is theamortized complexity: the worst case over a sequence of operations, rather than for a single operation.
We show that Henriksen's algorithm has an amortized complexity ofΘ(n 1/2) per insertion,O(1) per extract_min operation, andO(logn) for isolated deletions.
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