Problem      9011        9012

#     1                            I                     J
#     2                            A                    B
#     3                            G                    H
#     4                            A                    B
#     5                            F                     G
#     6                            I                      J
#     7                            G                    H
#     8                            J                     I
#     9                            B                    C
#    10                           C                    E
#    11                           B                    A
#    12                           J                    H