我自己的寫法是若出現A、B、C...三個以上的集合
請排成
A+B
A+C
A+D
B+C
B+D
C+D
A contain B
A does not contain C
A does not contain D
B does not contain A
B does not contain C
B contain D
C contain A
C contain B
C contain D
D does not contain A
D does not contain B
D contain C
我用這樣的順序寫是可以AC的