Branching in Digraphs with Many and Few Leaves: Structural and Algorithmic Results

  • Jørgen Bang-Jensen
  • Gregory GutinEmail author
Part of the Springer Optimization and Its Applications book series (SOIA, volume 139)


A subgraph T of a digraph D is called an out-tree if T is an oriented tree with just one vertex s of in-degree zero. A spanning out-tree is called an out-branching. A vertex x of an out-branching B is called a leaf if the out-degree of x is zero. This is a survey on out-branchings with minimum and maximum number of leaves covering both structural and algorithmic results.


Algorithmic Results Acyclic Digraph General Digraphs Input Digraph fixed-parameter Tractable (FPT) 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The research of Jørgen Bang-Jensen was supported by the Danish research council, grant number 1323-00178B. The research of Gregory Gutin was supported in part by Royal Society Wolfson Research Merit Award.


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.IMADA, University of Southern DenmarkOdense MDenmark
  2. 2.Department of Computer Science, Royal HollowayUniversity of LondonEgham, SurreyUK

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