(print (CNF '(jack and jill)))
(print (CNF '(hansel or gretel)))
(print (CNF '(simple)))
(print (CNF '(not hard)))
(print (CNF '(a implies b)))
(print (CNF '((a or b) or c)))
(print (CNF '(adam equivalent malakas)))
(print (CNF '((p implies (q or r)) and (not s))))
(print (CNF '((p implies (q and r)) and (not s))))
(print (CNF '((not (x or b)) equivalent ((not y) and (not (z implies a))))))