param n:=9;

param: V : C :=
	1 9
        2 5
        3 8
        4 4
	5 1
	6 3
	7 2
	8 7
	9 6;

set E :=
   (1,*) 2 3 4
   (2,*) 5 6 7
   (4,*) 8 9;

end;