Case 1: 4 Case 2: 2 Case 3: not possible Case 4: 3 Case 5: 4 Case 6: 4 Case 7: 2 Case 8: not possible Case 9: 4 Case 10: 4 Case 11: 10 Case 12: 5 Case 13: not possible Case 14: not possible Case 15: 2 Case 16: 4 Case 17: 4 Case 18: not possible Case 19: not possible