A sublinear space, polynomial time algorithm for directed s-t connectivity

  title={A sublinear space, polynomial time algorithm for directed s-t connectivity},
  author={Greg Barnes and Jonathan F. Buss and Walter L. Ruzzo and Baruch Schieber},
  journal={[1992] Proceedings of the Seventh Annual Structure in Complexity Theory Conference},
  • G. BarnesJonathan F. Buss B. Schieber
  • Published 22 June 1992
  • Computer Science, Mathematics
  • [1992] Proceedings of the Seventh Annual Structure in Complexity Theory Conference
A deterministic sublinear space, polynomial-time algorithm for directed s-t connectivity, which is the problem of detecting whether there is a path from vertex s to vertex t in a directed graph, is presented. For n-vertex graphs, the algorithm can use as little as n/2/sup Theta /( square root log n) space while still running in polynomial time.<<ETX>> 

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  • G. BarnesJ. Edmonds
  • Computer Science
    Proceedings of 1993 IEEE 34th Annual Foundations of Computer Science
  • 1993
A time-space lower bound is proved of ST=/spl Omega/(n/sup 2//log n) and S/sup 1/2/T /spl Omega/spl Omega for Cook and Rackoff's JAG model (1980), where n is the number of vertices and m the numberof edges in the input graph.


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