I do see a syntax error

Thanks, corrected. - I seem to just have learned something about index: use it! Did cut the wallclock time to the half it did... ;-) ... see my update.

In reply to Re^3: Challenge: prefix($x, $y) . suffix($x, $z) eq $x by shmem
in thread Challenge: prefix($x, $y) . suffix($x, $z) eq $x by Limbic~Region

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