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arXiv · 2603.17706

Biclique Reconfiguration in Bipartite Graphs

Yota Otachi·Emi Toyoda
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Abstract

We prove that Balanced Biclique Reconfiguration on bipartite graphs is PSPACE-complete. This implies the PSPACE-completeness of the spanning variant of Subgraph Reconfiguration under the token jumping rule for the property "a graph is an $(i, j)$-complete bipartite graph," which was previously known only to be NP-hard [Hanaka et al. TCS 2020]. Using our result, we also show that Connected Components Reconfiguration with two connected components is PSPACE-complete under all previously studied rules, resolving an open problem of Nakahata [COCOON 2025] in the negative.

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Yota Otachi, Emi Toyoda. 2026-03-18. Biclique Reconfiguration in Bipartite Graphs. https://arxiv.org/abs/2603.17706

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