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arXiv · 1507.03209

On the complexity of the chip-firing reachability problem

Bálint Hujter·Viktor Kiss·Lilla Tóthmérész
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Abstract

In this paper, we study the complexity of the chip-firing reachability problem. We show that for Eulerian digraphs, the reachability problem can be decided in strongly polynomial time, even if the digraph has multiple edges. We also show a special case when the reachability problem can be decided in polynomial time for general digraphs: if the target distribution is recurrent restricted to each strongly connected component. As a further positive result, we show that the chip-firing reachability problem is in co-NP for general digraphs. We also show that the chip-firing halting problem is in co-NP for Eulerian digraphs.

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Bálint Hujter, Viktor Kiss, Lilla Tóthmérész. 2015-07-12. On the complexity of the chip-firing reachability problem. https://doi.org/10.1090/proc/13498

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