论文信息 - Universal Traversal Sequences for Expander Graphs

Universal Traversal Sequences for Expander Graphs

Graph reachability is a key problem in the study of various logarithmic space complexity classes. Its version for directed graphs is logspace complete for NSPACE(logn), and hence if proved to be in DSPACE(logn), the open question DSPACE(logn) = NSPACE(log n) will be settled. Seemingly the problem is easier for undirected graphs. In [1] it was shown to be in RLP (1-sided error, logspace, polynomial expected time). Recently it was shown by [3] to be in ZPLP (no-error, logspace, polynomial expected time).

Avi Wigderson | Shlomo Hoory

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