Another way.

$ perl -Mstrict -Mwarnings -E '
say join q{-}, do {
   my %seen;
   grep { not $seen{ $_ } ++ } split m{-};
   } for qw{
      12-12
      12-12-12
      12-13-12-13
      12-12-13-13
      12-13-13-14
      };'
12
12
12-13
12-13
12-13-14
$

[download]

I hope this is helpful.

Cheers,

JohnGG

In reply to Re: How can I reduce this with a REGEX? by johngg
in thread How can I reduce this with a REGEX? by misterperl

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