my $a = join("", $types[0][ map { rand \$types[0] } ( 1 .. 4 ) ]);
$a .= join("", $types[1][ map { rand \$types[1] } ( 1 .. 4 ) ]);
$a .= join("", $types[2][ map { rand \$types[2] } ( 1 .. 4 ) ]);
$a .= join("", $types[3][ map { rand \$types[3] } ( 1 .. 4 ) ]);