Determining Single Connectivity in Directed Graphs
نویسندگان
چکیده
In this paper, we consider the problem of determining whether or not a directed graph contains a pair of vertices connected by two distinct simple paths; if it does not, we say it is singly connected. A straightforward implementation using n depth rst searches requires O(nm) time on an n-vertex, m-arc digraph; we obtain an O(n) time algorithm by using contraction wherever possible. Supported by a Fannie and John Hertz Foundation fellowship, National Science Foundation Grant No. CCR-8920505, and the Center for Discrete Mathematics and Theoretical Computer Science (DIMACS) under NSF-STC88-09648. 2Supported by a National Science Foundation Graduate Fellowship and the Fannie and John Hertz Foundation.
منابع مشابه
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