1 9 1 A - 5 B B 7 A B 8 - A 9 C B 12 A A 16 B - 17 C - 18 B B 9 1 - A 2 B B 3 A B 4 - A 6 C B 8 A - 10 B B 16 - B 17 - B
Case 1: 1 A A 2 B B 3 A B 4 - A 5 B B 6 C B 7 A B 8 A A 9 C B 10 B B 12 A A 16 B B 17 C B 18 B B