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A Parameterized Perspective on $P_2$-Packings

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 نشر من قبل Daniel Raible
 تاريخ النشر 2008
  مجال البحث الهندسة المعلوماتية
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}We study (vertex-disjoint) $P_2$-packings in graphs under a parameterized perspective. Starting from a maximal $P_2$-packing $p$ of size $j$ we use extremal arguments for determining how many vertices of $p$ appear in some $P_2$-packing of size $(j+1)$. We basically can reuse $2.5j$ vertices. We also present a kernelization algorithm that gives a kernel of size bounded by $7k$. With these two results we build an algorithm which constructs a $P_2$-packing of size $k$ in time $Oh^*(2.482^{3k})$.



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