3
ABCDEFGHIJ
5
A -> I
AB -> C
AD -> GH
BD -> EF
H -> J
BD
ABCDEFGH
6
A -> BC
C -> D
D -> G
E -> A
E -> H
H -> E
AC
ABCDEFG
7
A -> F
A -> G
B -> E
C -> D
D -> B
E -> A
FG -> C
FG
