I 0 0 N N d c b a
I
N
0 0 N N d c b a
l h h
k g g
j f f
i e e
h d d
g c c
f b b
e a a
I 0 0 N N d c b a
N
l l
k k
k l
k k
j j
i j
i i
i k
g h
g g
g i
g g
F f f
F e
F F
F g
4 F F
E f e
E g
2 E E
e e
f e
f f
f g
f f
e g
0 I I F 4 e 2 f
0 I I f E 2 0 0
0 0 0 0 I 0 I 0
I 0 0 N e d c b a
I