#usage: perl multimap.pl <input> <output>

$input = $ARGV[0];
$output = $ARGV[1];
$tmp = "$output.tmp";

open FILE, $input;
while (<FILE>) {
	$a = join(" ", $_);
	@b = split /\s+/, $a;
	@c = grep /^HWI/, @b;
	open FILE2, ">>$tmp";
	select FILE2;
	printf "@c\n";
}
close FILE;
close FILE2;
open FILE2, $tmp;
while (<FILE2>) { 		
    $e{$_}++ for $_;
}
close FILE2;
unlink("$tmp");
open FILE3, ">>$output";
select FILE3;
while (($key, $value) = each(%e)){
	if ($value > 1) {
    	printf "$value $key";
    }
}
close FILE3;