,
Ryoga Mahara
,
Tamás Schwarcz
Creative Commons Attribution 4.0 International license
An arborescence in a digraph is an acyclic arc subset in which every vertex except a root has exactly one incoming arc. In this paper, we show the reconfigurability of the union of k arborescences for fixed k in the following sense: for any pair of arc subsets that can be partitioned into k arborescences, one can be transformed into the other by exchanging arcs one by one so that every intermediate arc subset can also be partitioned into k arborescences. This generalizes the result by Ito et al. (2023), who showed the case with k = 1. Since the union of k arborescences can be represented as a common matroid basis of two matroids, our result gives a new non-trivial example of matroid pairs for which two common bases are always reconfigurable to each other.
@InProceedings{kobayashi_et_al:LIPIcs.ISAAC.2023.48,
author = {Kobayashi, Yusuke and Mahara, Ryoga and Schwarcz, Tam\'{a}s},
title = {{Reconfiguration of the Union of Arborescences}},
booktitle = {34th International Symposium on Algorithms and Computation (ISAAC 2023)},
pages = {48:1--48:14},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-289-1},
ISSN = {1868-8969},
year = {2023},
volume = {283},
editor = {Iwata, Satoru and Kakimura, Naonori},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ISAAC.2023.48},
URN = {urn:nbn:de:0030-drops-193502},
doi = {10.4230/LIPIcs.ISAAC.2023.48},
annote = {Keywords: Arborescence packing, common matroid basis, combinatorial reconfiguration}
}