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I need an algorithm for determining the order of a list of items, based on their occurrence in a file, without knowing the elements of the list ahead of time. The list is repeated multiple times in the file, but each time some elements may be missing. Order is always preserved. Each instance of the list in the file has a start marker. Here is an example list:
Alpha Beta Gamma Delta Epsilon Zeta
If each list instance is marked with Start, here is an example sequence in a file:
Start Alpha Beta Start Epsilon Zeta Start Beta Gamma Zeta Start Alpha Gamma Delta Epsilon
After I read the file, I just need to dump the list in order. It is possible that some files may be indeterminate. For example, given:
Start Alpha Beta Start Alpha Gamma
the order of Beta and Gamma cannot be determined. I just need to make note of this, issue a warning, and then assign an arbitrary order.

I'm not looking for working code, just some ideas to get started.

-QM
--
Quantum Mechanics: The dreams stuff is made of


In reply to Reconstructing List Order From Partial Subsets by QM

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