50
A	A	1
A	B	25
B	A	1
B	C	24
C	A	1
C	D	23
D	A	1
D	E	22
E	A	1
E	F	21
F	A	1
F	G	20
G	A	1
G	H	19
H	A	1
H	I	18
I	A	1
I	J	17
J	A	1
J	K	16
K	A	1
K	L	15
L	A	1
L	M	14
M	A	1
M	N	13
N	A	1
N	O	12
O	A	1
O	P	11
P	A	1
P	Q	10
Q	A	1
Q	R	9
R	A	1
R	S	8
S	A	1
S	T	7
T	A	1
T	U	6
U	A	1
U	V	5
V	A	1
V	W	4
W	A	1
W	X	3
X	A	1
X	Y	2
Y	A	1
Y	Z	1