Local Search for String Problems: Brute Force Is Essentially Optimal

  • Jiong Guo
  • Danny Hermelin
  • Christian Komusiewicz
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7922)


We address the problem of whether the brute-force procedure for the local improvement step in a local search algorithm can be substantially improved when applied to classical NP-hard string problems. We examine four problems in this domain: Closest String, Longest Common Subsequence, Shortest Common Supersequence, and Shortest Common Superstring. Herein, we consider arguably the most fundamental string distance measure, namely the Hamming distance, which has been applied in practical local search implementations for string problems. Our results indicate that for all four problems, the brute-force algorithm is essentially optimal.


Local Search Close String Local Search Algorithm Solution String Color Class 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Jiong Guo
    • 1
  • Danny Hermelin
    • 2
  • Christian Komusiewicz
    • 3
  1. 1.Universität des SaarlandesSaarbrückenGermany
  2. 2.Department of Industrial Management and EngineeringBen-Gurion UniversityBeer ShevaIsrael
  3. 3.Institut für Softwaretechnik und Theoretische InformatikTechnische Universität BerlinBerlinGermany

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