Did M1 and M4 marry a screenwriter and influence M2 and M3
SELECT count(*) WHERE {
?x0 a ns:film.writer .
FILTER ( M1 != ?x0 ) .
FILTER ( M4 != ?x0 ) .
M1 ns:influence.influence_node.influenced M2 .
M1 ns:influence.influence_node.influenced M3 .
M1 ns:people.person.spouse_s/ns:people.marriage.spouse|ns:fictional_universe.fictional_character.married_to/ns:fictional_universe.marriage_of_fictional_characters.spouses ?x0 .
M4 ns:influence.influence_node.influenced M2 .
M4 ns:influence.influence_node.influenced M3 .
M4 ns:people.person.spouse_s/ns:people.marriage.spouse|ns:fictional_universe.fictional_character.married_to/ns:fictional_universe.marriage_of_fictional_characters.spouses ?x0
}