Presumably you've code the obvious two loops method and it is taking too long. Could you supply a timing for one of your datasets?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^3: list of unique strings, also eliminating matching substrings by BrowserUk
in thread list of unique strings, also eliminating matching substrings by lindsay_grey

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