A
S
C
D
A
C
S
A
D
B
D
B
C
A
A
A
C
C
B
S
S
S
D
A
A
B
A
A
C
S
A
B
B
S
D
B
C
B
C
C
S
D
B
D
A
B
D
B
D
D
S
A
S
C
B
S
C
B
D
C
A
C
S
C
A
B
B
A
S
D
S
D
S
B
A
S
D
D
D
S
C
D
C
B