D
R
D
O
F
R
R
O
O
D
X
F
F
R
R
D
X
D
O
O
X
X
O
O
R
F
X
R
D
O
X
R
X
R
D
D
X
O
X
O
O
D
R
O
D
D
F
X
O
X
F
O
F
X
F
D
D
R
F
F
R
X
F
O
F
F
F
R
D
X
R
D
R
F
X