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arXiv · 2503.17264

A 3.3904-Competitive Online Algorithm for List Update with Uniform Costs

Mateusz Basiak·Marcin Bienkowski·Martin Böhm·Marek Chrobak·Łukasz Jeż·Jiří Sgall·Agnieszka Tatarczuk
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Abstract

We consider the List Update problem where the cost of each swap is assumed to be 1. This is in contrast to the ``standard'' model, in which an algorithm is allowed to swap the requested item with previous items for free. We construct an online algorithm Full-Or-Partial-Move (FPM), whose competitive ratio is at most $3.3904$, improving over the previous best known bound of $4$.

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Mateusz Basiak, Marcin Bienkowski, Martin Böhm, Marek Chrobak, Łukasz Jeż, Jiří Sgall, Agnieszka Tatarczuk. 2025-03-21. A 3.3904-Competitive Online Algorithm for List Update with Uniform Costs. https://arxiv.org/abs/2503.17264

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