Network search with inadmissible heuristics
A new arc-marking algorithm, namely MarkC is presented. MarkC uses the run-time heuristic modification scheme (due to Mero), and the node selection criterion of AlgorithmC (due to Bagchi and Mahanti). AlgorithmC, based on the node expansion scheme, has some important properties under general inadmissible heuristics. AlgorithmC always finds a least costly solution path of V (an implicitly defined set of nodes) and makes O(N2) node expansions at the worst. It is shown that MarkC retains all the merits of C, yet it does not iterate more number of times than C. But there are examples where C can make some more iterations than MarkC. Finally, a comparative study is presented by summarizing the results on Algorithms MarkA, C, and MarkC.
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