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📃Scientific paper: Faster parameterized algorithms for modification problems to minor-closed classes Abstract: Let G be a minor-closed graph class and let G be an n-vertex graph. We say that G is a k-apex of G if G contains a set S of at most k vertices such that G \ S belongs to G. Our first result is an algorithm that decides whether G is a k-apex of G in time 2 poly\(k\) • n 2. This algorithm improves the previous one, given by Sau, Stamoulis, and Thilikos \[ICALP 2020, TALG 2022\], whose running time was 2 poly\(k\) • n^3. The elimination distance of G to G, denoted by edG\(G\), is the minimum number of rounds required to reduce each connected component of G to a graph in G by removing one vertex from each connected component in each round. Bulian and Dawar \[Algorithmica 2017\] proved the existence of an FPT-algorithm, with parameter k, to decide whether edG\(G\) ≤ k. This algorithm is based on the computability of the minor-obstructions and its dependence on k is not explicit. We extend the techniques used in the first algorithm to decide whether edG\(G\) ≤ k in time 2^2^2^poly\(k\) • n^2. This is the first algorithm for this problem with an explicit parametric dependence in k. In the special case where G excludes some apex-graph as a minor, we give two alternative algorithms, one running in time 2^2^O\(k 2 log k\) • n 2 and one running in time 2 poly\(k\) • n^3. As a stepping stone for these algorithms, we provide an algorithm that decides whether edG\(G\) ≤ k in time 2 O\(tw•k+tw log tw\) • n, where tw is the treewidth of G. This algorithm combines the dynamic programming framework of Re... Continued on ES/IODE ➡️ https://etcse.fr/HZS ------- If you find this interesting, feel free to follow, comment and share. We need your help to enhance our visibility, so that our platform continues to serve you.

Faster parameterized algorithms for modification problems to minor-closed classes

Faster parameterized algorithms for modification problems to minor-closed classes

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