That sounds like O (n * n!) indeed. It looks like you are trying to find a hamiltonian path through a graph where the nodes of the graph correspond to the string in your set, and there's an edge between a pair of nodes if, and only if, the corresponding strings differ by a single transposition.

The general problem of finding an hamiltonian path is NP-complete, but for specific graphs it might be easier.

Abigail

In reply to Re: Detecting transpositions by Abigail-II
in thread Detecting transpositions by BrowserUk

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