A B 4 F 3
B C 4 D 1 E 3
C E 2
D A 2 F 2 G 3
E G 2 H 2
F D 1 I 1
G I 2 J 3
H C 3 J 1
I L 3 N 2
J E 3 L 2
K F 4 I 1 N 2 P 2
L J 1
M H 3 J 2 R 3
N L 2 Q 3
O L 2 M 1
P N 1
Q L 1 O 1
R O 2