Noga Alon, Daniel Lokshtanov, Saket Saurabh

Research output: Chapter in Book/Report/Conference proceedingConference contribution

80 Scopus citations


We present a randomized subexponential time, polynomial space parameterized algorithm for the k -Weighted Feedback Arc Set in Tournaments (k -FAST) problem. We also show that our algorithm can be derandomized by slightly increasing the running time. To derandomize our algorithm we construct a new kind of universal hash functions, that we coin universal coloring families. For integers m,k and r, a family of functions from [m] to [r] is called a universal (m,k,r)-coloring family if for any graph G on the set of vertices [m] with at most k edges, there exists an which is a proper vertex coloring of G. Our algorithm is the first non-trivial subexponential time parameterized algorithm outside the framework of bidimensionality.

Original languageEnglish (US)
Title of host publicationAutomata, Languages and Programming - 36th International Colloquium, ICALP 2009, Proceedings
Number of pages10
EditionPART 1
StatePublished - 2009
Externally publishedYes
Event36th International Colloquium on Automata, Languages and Programming, ICALP 2009 - Rhodes, Greece
Duration: Jul 5 2009Jul 12 2009

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
NumberPART 1
Volume5555 LNCS
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


Other36th International Colloquium on Automata, Languages and Programming, ICALP 2009

All Science Journal Classification (ASJC) codes

  • Theoretical Computer Science
  • General Computer Science


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