A near optimal algorithm for the extended cow-path problem in the presence of relative errors

  • Pallab Dasgupta
  • P. P. Chakrabarti
  • S. C. DeSarkar
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1026)


In classical path finding problems, the cost of a search function is simply the number of queries made to an oracle that knows the position of the goal. In many problems, we want to charge a cost proportional to the distance between queries (e.g., the time required to travel between two query points). With this cost function in mind, the original w-lane cow-path problem [8] was modeled as a navigation problem in a terrain which consists of w-concurrent avenues. In this paper we study a variant of this problem where the terrain is an uniform b-ary tree, and there is a lower-bound estimate of the cost function. We present a strategy CowP for this class of problems where the relative error is bounded by a known constant and show that its worst case complexity is less than or equal to [4b/(b−1)] times optimal.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

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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