#!/usr/bin/perl
use strict;
use warnings;

my $OUTPATH='';
my $A='';
my $B='';
my $C='';


open(my $temp_fh, '<', "$OUTPATH/$B") or die("Can't open $B ($!)\n");
my @referenz=<$temp_fh>;
close($temp_fh);

open(my $out_fh, '>', "$OUTPATH/$C") or die("Can't open $C ($!)\n");
open(my $in_fh,  '<', "$OUTPATH/$A") or die("Can't open $A ($!)\n");
MAINLOOP:
while(my $line = <$in_fh>)
{
  my $value=substr($line,0,20);
  $value+=0;
  
  for my $ref_line (@referenz)
  {
    if($ref_line =~ /$value/)
    {
      print $out_fh $ref_line;
      next MAINLOOP;
    }
  }
  
  print $out_fh $line;
}
close($in_fh);
close($out_fh);