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arXiv · 2104.11383

$\Gamma$-graphic delta-matroids and their applications

Donggyu Kim·Duksang Lee·Sang-il Oum
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Abstract

For an abelian group $\Gamma$, a $\Gamma$-labelled graph is a graph whose vertices are labelled by elements of $\Gamma$. We prove that a certain collection of edge sets of a $\Gamma$-labelled graph forms a delta-matroid, which we call a $\Gamma$-graphic delta-matroid, and provide a polynomial-time algorithm to solve the separation problem, which allows us to apply the symmetric greedy algorithm of Bouchet to find a maximum weight feasible set in such a delta-matroid. We present two algorithmic applications on graphs; Maximum Weight Packing of Trees of Order Not Divisible by $k$ and Maximum Weight $S$-Tree Packing. We also discuss various properties of $\Gamma$-graphic delta-matroids.

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Donggyu Kim, Duksang Lee, Sang-il Oum. 2021-04-23. $\Gamma$-graphic delta-matroids and their applications. https://doi.org/10.1007/s00493-023-00043-6

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