use 5.010;
use List::MoreUtils qw< part >;

say for
	map {
		my $x = $_;
		sprintf(
			'%s %d,%d',
			$x->[0][0],
			scalar(grep { $_->[1] eq '1_x' } @$x),
			scalar(grep { defined $_->[2] } @$x), 
		)
	}
	part {
		# me thinks List::MoreUtils needs a way to make this simpler
		state $part = 0;
		state $last = undef;
		$part++ if defined $last && $last ne $_->[0];
		$last = $_->[0];
		$part
	}
	map { chomp; [split /\s+/] }
	sort <DATA>;

__DATA__
A 1_x 9_z
A 1_x 
A 1_x g_z
B 2_c 
B 1_x 1_z
C 1_x 1_z
C v_x 8_z