S
U
B
U
B
R
U
R
B
C
C
S
R
B
S
U
S
R
U
R
C
U
U
R
S
C
C
C
R
B
C
B
U
R
R
S
C
S
U
B
S
C
S
U
R
U
B
B
C
S
C
B
R
B