#!usr\bin\perl -w open HUBFILE,"1048_undefined.tsv"; @hub=(); while(my $line = ){ while ($line =~ /\d \t (\w+) \t/x) { push(@hub,$1); } }close HUBFILE; $L=@hub; open OUT,">hubs.txt"; for($i=0;$i<$L;$i++){ print OUT "HUB:$hub[$i]\n"; } close OUT;