{ "id": "2503.13112", "version": "v2", "published": "2025-03-17T12:34:42.000Z", "updated": "2025-05-15T14:07:16.000Z", "title": "Connected Partitions via Connected Dominating Sets", "authors": [ "Aikaterini Niklanovits", "Kirill Simonov", "Shaily Verma", "Ziena Zeif" ], "categories": [ "math.CO", "cs.DS" ], "abstract": "The classical theorem due to Gy\\H{o}ri and Lov\\'{a}sz states that any $k$-connected graph $G$ admits a partition into $k$ connected subgraphs, where each subgraph has a prescribed size and contains a prescribed vertex, as long as the total size of target subgraphs is equal to the size of $G$. However, this result is notoriously evasive in terms of efficient constructions, and it is still unknown whether such a partition can be computed in polynomial time, even for $k = 5$. We make progress towards an efficient constructive version of the Gy\\H{o}ri--Lov\\'{a}sz theorem by considering a natural strengthening of the $k$-connectivity requirement. Specifically, we show that the desired connected partition can be found in polynomial time, if $G$ contains $k$ disjoint connected dominating sets. As a consequence of this result, we give several efficient approximate and exact constructive versions of the original Gy\\H{o}ri--Lov\\'{a}sz theorem: 1. On general graphs, a Gy\\H{o}ri--Lov\\'{a}sz partition with $k$ parts can be computed in polynomial time when the input graph has connectivity $\\Omega(k \\cdot \\log^2 n)$; 2. On convex bipartite graphs, connectivity of $4k$ is sufficient; 3. On biconvex graphs and interval graphs, connectivity of $k$ is sufficient, meaning that our algorithm gives a ``true'' constructive version of the theorem on these graph classes.", "revisions": [ { "version": "v2", "updated": "2025-05-15T14:07:16.000Z" } ], "analyses": { "keywords": [ "connected partition", "polynomial time", "convex bipartite graphs", "connectivity requirement", "efficient constructive version" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }