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arXiv · 2312.01857

A note on the complexity of the picker routing problem in multi-block warehouses and related problems

Thibault Prunet·Nabil Absi·Diego Cattaruzza
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Abstract

The Picker Routing Problem (PRP), which consists of finding a minimum-length tour between a set of storage locations in a warehouse, is one of the most important problems in the warehousing logistics literature. Despite its popularity, the tractability of the PRP in multi-block warehouses remains an open question. This technical note aims to fill this research gap by establishing that the problem is strongly NP-hard. As a corollary, the complexity status of other related problems is settled.

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Thibault Prunet, Nabil Absi, Diego Cattaruzza. 2023-12-04. A note on the complexity of the picker routing problem in multi-block warehouses and related problems. https://doi.org/10.1007/s10479-025-06481-3

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