STACS 2005: STACS 2005 pp 36-43 | Cite as

Algorithmics in Exponential Time

  • Uwe Schöning
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3404)

Abstract

Exponential algorithms, i.e. algorithms of complexity O(c n ) for some c > 1, seem to be unavoidable in the case of NP-complete problems (unless P=NP), especially if the problem in question needs to be solved exactly and not approximately. If the constant c is close to 1 such algorithms have practical importance. Deterministic algorithms of exponential complexity usually involve some kind of backtracking. The analysis of such backtracking algorithms in terms of solving recurrence equations is quite well understood. The purpose of the current paper is to show cases in which the constant c could be significantly reduced, and to point out that there are some randomized exponential-time algorithms which use randomization in some new ways. Most of our examples refer to the 3-SAT problem, i.e. the problem of determining satisfiability of formulas in conjunctive normal form with at most 3 literals per clause.

Keywords

Local Search Conjunctive Normal Form Exponential Time Recursive Call Boolean Formula 
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.
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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Uwe Schöning
    • 1
  1. 1.Abteilung Theoretische InformatikUniversität UlmUlmGermany

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