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arXiv · 2610.32721

Deterministic Incremental Triconnectivity in $O(\log^2 n)$ Worst-Case Time

Niels Inselmann Christiansen·Eva Rotenberg
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Abstract

We consider the problem of maintaining the triconnectivity in some biconnected graph G in the incremental dynamic setting. We consider updates in the form of edge insertions and edge subdivisions, and triconnectivity queries, i.e. queries of the form "are there at least three vertex disjoint paths between a and b?". All algorithms presented in this paper are deterministic. All queries and updates are answered in worst-case $O(\log n)$ time. By combining this result for biconnected graphs with a result of Holm and Rotenberg [SODA'20] we get an algorithm for general graphs with a worst-case running time of $O(\log^2 n)$ per operation. These algorithms represent an improvement of the state-of-the-art by a factor of $O(\log n)$.

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Niels Inselmann Christiansen, Eva Rotenberg. 2026-10-23. Deterministic Incremental Triconnectivity in $O(\log^2 n)$ Worst-Case Time. https://arxiv.org/abs/2610.32721

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