TY - GEN

T1 - Algorithms for k-internal out-branching

AU - Zehavi, Meirav

PY - 2013/12/1

Y1 - 2013/12/1

N2 - The k-Internal Out-Branching (k-IOB) problem asks if a given directed graph has an out-branching (i.e., a spanning tree with exactly one node of in-degree 0) with at least k internal nodes. The k-Internal Spanning Tree (k-IST) problem is a special case of k-IOB, which asks if a given undirected graph has a spanning tree with at least k internal nodes. We present an O*(4 k) time randomized algorithm for k-IOB, which improves the O* running times of the best known algorithms for both k-IOB and k-IST. Moreover, for graphs of bounded degree Δ, we present an O*(2 (2-Δ+1/Δ(Δ-1))k) time randomized algorithm for k-IOB. Both our algorithms use polynomial space.

AB - The k-Internal Out-Branching (k-IOB) problem asks if a given directed graph has an out-branching (i.e., a spanning tree with exactly one node of in-degree 0) with at least k internal nodes. The k-Internal Spanning Tree (k-IST) problem is a special case of k-IOB, which asks if a given undirected graph has a spanning tree with at least k internal nodes. We present an O*(4 k) time randomized algorithm for k-IOB, which improves the O* running times of the best known algorithms for both k-IOB and k-IST. Moreover, for graphs of bounded degree Δ, we present an O*(2 (2-Δ+1/Δ(Δ-1))k) time randomized algorithm for k-IOB. Both our algorithms use polynomial space.

UR - http://www.scopus.com/inward/record.url?scp=84893148036&partnerID=8YFLogxK

U2 - 10.1007/978-3-319-03898-8_30

DO - 10.1007/978-3-319-03898-8_30

M3 - Conference contribution

AN - SCOPUS:84893148036

SN - 9783319038971

T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

SP - 361

EP - 373

BT - Parameterized and Exact Computation - 8th International Symposium, IPEC 2013, Revised Selected Papers

T2 - 8th International Symposium on Parameterized and Exact Computation, IPEC 2013

Y2 - 4 September 2013 through 6 September 2013

ER -