SELECT DISTINCT VE1.V
FROM VE AS VE1
WHERE NOT EXISTS
	(SELECT * FROM VE AS VE2
	WHERE VE2.V = 1
	AND VE2.E NOT IN
		(SELECT VE3.E
		FROM VE AS VE3
		WHERE VE1.V = VE3.V))
AND NOT EXISTS
	(SELECT *
	FROM VE AS VE3
	WHERE VE1.V = VE3.V
	AND VE3.E NOT IN
		(SELECT VE4.E
		FROM VE AS VE4
		WHERE VE4.V = 1));