Solving the ANTS Problem with Asynchronous Finite State Machines

  • Yuval Emek
  • Tobias Langner
  • Jara Uitto
  • Roger Wattenhofer
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8573)


Consider the Ants Nearby Treasure Search (ANTS) problem introduced by Feinerman, Korman, Lotker, and Sereni (PODC 2012), where n mobile agents, initially placed in a single cell of an infinite grid, collaboratively search for an adversarially hidden treasure. In this paper, the model of Feinerman et al. is adapted such that each agent is controlled by an asynchronous (randomized) finite state machine: they possess a constant-size memory and can locally communicate with each other through constant-size messages. Despite the restriction to constant-size memory, we show that their collaborative performance remains the same by presenting a distributed algorithm that matches a lower bound established by Feinerman et al. on the run-time of any ANTS algorithm.


Grid Cell Mobile Agent Full Version Cardinal Direction Emission Function 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Yuval Emek
    • 1
  • Tobias Langner
    • 2
  • Jara Uitto
    • 2
  • Roger Wattenhofer
    • 2
  1. 1.TechnionIsrael
  2. 2.ETH ZürichSwitzerland

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