D
X
X
N
N
O
D
R
R
O
R
O
X
O
O
O
D
N
D
R
N
D
N
D
X
X
N
N
N
R
X
N
D
X
R
N
D
N
D
D
R
O
O
N
X
D
O
N
R
R
X
D
X
R
O
X
X
N
R
O
X
R
X
X
D
R
R
O
N
D
D
O
O
O