A new competitive algorithm for agent searching in unknown streets

  • Pallab Dasgupta
  • P. P. Chakrabarti
  • S. C. DeSarkar
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1180)


In this paper we present a simple on-line strategy based on a continuous angle bisector approach for searching an unknown street polygon. The proposed strategy achieves a competitive ratio of 1+loge(1+ cos α/2)+δ, where 0≤απ, and δ is a given constant greater than zero. By choosing an arbitrarily small value for δ, the value of this ratio is 1.7, which is significantly better than the previous upperbound of 2.83 (derived by Kleinberg [6]), considering that the lowerbound for this problem is √2(> 1.41) (derived by Klein [5]).


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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • Pallab Dasgupta
    • 1
  • P. P. Chakrabarti
    • 1
  • S. C. DeSarkar
    • 1
  1. 1.Dept. of Computer Sc. & Engg.Indian Institute of TechnologyKharagpurIndia

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