_ A D A C B _ _ B D C C 2 6 _ _ 2 4 8 4_ _ _ _ a _ _ b _ _ c d ? ? ? ?
d, c, a, a
_ A D A C B _ _ B D C C
2 6 _ _ 2 4 8 4 _ _ _ _
a _ _ b _ _ c d _ _ _ _
By comparing each of capital letters, numbers and small letters, we get
C - 2 - a
A - 6 - b
B - 4 - d
D - 8 - c