It seems that you're just trying to remove all whitespaces: 
s/\s+//g;

[download]

Of course that doesn't verify your data, so you could use split instead (untested): 

OUTER:
while (<>){
   chomp;
   my @items = split m/\s/;
   for my $i (@items) {
       last OUTER unless $i =~ m/^[a-f\d]{2}$/;
   }
   print join '', @items;
}

[download]

In reply to Re: Help with parsing a string by moritz
in thread Help with parsing a string by sdolancu

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