An efficient implementation of parallel A*

  • Van -Dat Cung
  • Bertrand Le Cun
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 805)


This paper presents a new parallel implementation of the heuristic state space search A* algorithm. We show the efficiency of a new utilization of data structure the treap, instead of traditional priority queues (heaps). This data structure allows operations such as Insert, DeleteMin and Search which are essential in the A* algorithm. Furthermore, we give concurrent algorithm of the treap within a shared memory environment. Results on the 15 puzzle are presented; they have been obtained on two machines, with virtual or not shared memory, the KSR1 and the Sequent Balance 8000.


Heuristic search A* data structure binary search tree priority queue parallelism concurrence 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1994

Authors and Affiliations

  • Van -Dat Cung
    • 1
    • 2
  • Bertrand Le Cun
    • 1
    • 2
  1. 1.Laboratoire PRiSMUniversité de VersaillesVersaillesFrance
  2. 2.INRIA-RocquencourtLe Chesnay CedexFrance

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