my %faclist;
my $i;

open(DATA, "AXP_FACS.DAT");
while(<DATA>){
        my $line = $_;
        $faclist{$line} = "";
}
close(DATA);

for ($i=1;$i<5001;$i++){
        if exists $faclist{$i}{#THIS IS WHERE THE PROBLEM IS
                print "$i\n";
        }
}