Were M1 and M2 directed and edited by M0 's editor
SELECT count(*) WHERE {
?x0 ns:film.editor.film M0 .
M1 ns:film.film.directed_by ?x0 .
M1 ns:film.film.edited_by ?x0 .
M2 ns:film.film.directed_by ?x0 .
M2 ns:film.film.edited_by ?x0
}