Online algorithms for topological order and strongly connected components
نویسندگان
چکیده
We consider how to maintain the topological order of a directed acyclic graph (DAG) in the presence of edge insertions and deletions. We present a new algorithm and obtain a marginally improved complexity result over the previously known O(||δ||log||δ||). In addition, we provide an empirical comparison against three existing solutions using random DAG’s. The results show our algorithm to out perform the others on sparse graphs. Finally, we show how the algorithm can be extended to identify strongly connected components online. Our motivation for this work arises from efforts to build efficient pointer analyses, where identifying cycles in a dynamic graph has a significant impact on performance.
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