Concurrent Computations pp 117-138 | Cite as

# Fast Parallel Algorithms for Reducible Flow Graphs

Chapter

## Abstract

We give parallel NC algorithms for recognizing reducible flow graphs (rfg’s), and for finding dominators, minimum feedback vertex sets, and a depth first search numbering in an rfg. We show that finding a minimum feedback vertex set in vertex-weighted rfg’s or finding a minimum feedback arc set in arc-weighted rfg’s is P-complete. We present RNC algorithms for finding a minimum feedback arc set in an unweighted rfg, and for finding a minimum weight feedback set when arc or vertex weights are in unary; and we show that these problems are in NC if and only if the maximum matching problem is in NC.

## Keywords

Flow Graph Minimum Feedback Tree Contraction Depth First Search Tree EREW Pram
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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© Plenum Press, New York 1988