I am assuming you are talking about the files in said dir being sorted alphabetically. With that you could alter the push to something along the lines of

Update: I've been thinking about my solution, and I think the latter one is more appropriate, as opposed to the first. Im sure a better search criterion to File::Find would be more efficient way to go about doing this.

   push(@nod, $_) if m/^[a-cA-C]/;
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   return unless m/^[a-cA-C]/;
   push(@nod, $_);
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