25
AB 1 1
BC 1 1
CD 1 1
DE 1 1
EF 1 1
FG 1 1
GH 1 1
HI 1 1
IJ 1 1
JK 1 1
KL 1 1
LM 1 1
MN 1 1
NO 1 1
OP 1 1
PQ 1 1
QR 1 1
RS 1 1
ST 1 1
TU 1 1
UV 1 1
VW 1 1
WX 1 1
XY 1 1
YZ 1 1