digraph T {
	t1->t2 [LABEL="a"]
	t2->t3 [LABEL="c"]
	t4->t1 [LABEL="b"]
	t3->t4 [LABEL="a"]
	t2->t2 [LABEL="b"]
	t2->t2 [LABEL="ciao"]
	[initial={t1}]
	[final={t1}]
}


	
