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shortest-pathnp-completereduction

Simple reduction (NP completeness)


I'm looking for a means to prove that the bicriteria shortest path problem is np complete. That is, given a graph with lengths and weights, I need to know if a there exists a path in the graph from s to t with total length <= L and weight <= W.

I know that i must take an NP complete problem and reduce it to this one. We have at our disposal the following problems to choose from: 3-SAT, independent set, vertex cover, hamiltonian cycle, and 3-dimensional matching.

Any ideas on which may be viable?

thanks


Solution

  • Did you try Google? 3rd hit is:

    http://www.jstage.jst.go.jp/article/ieejeiss/128/3/128_416/_article

    The article is pay-per-view, but the Google cache supplies the important bit upfront:

    "Unfortunately, the multiobjective case ( including the bicriteria case) is NP-complete(3).

    and the reference points to:

    (3) M. Garey and D. Johnson : Computers, and Intractability : A Guide to the theory of NP-Completeness, New York: Freeman (1979)

    which is the standard reference for questions of this form.

    So ... have you looked at Garey and Johnson? I don't have a copy here to check, but it was my go-to when I did comps.