rhxk,
Your original title was misleading, but has been edited. You want the total number of X in all the elements of a list. This sub should give you an idea of how to make it general. Since others have complained about not making an effort or possibly being homework, I have obfu'd it a bit.

sub Count {
    my $t;
    for ( @_[1..$#_] ) { ($t) += grep {$_ eq $_[0] } split // }
    return $t;
}
[download]

Cheers - L~R

Update Modified to reflect title change by editors