f NCTF
a b c d d e f f g g h h h a a a a
b b b
b b b b b a a a a h h h h g g f f
g g e
d c b h f c h f d a f d a d
a f c
g d a f c g d a e b f c g d h
d a e
a f b f b f g b f b e a d h c
g b e
a d h c b f a e h d e b f b f
b f a
e a e h d h c f b f b a g c g
d h d
h d h d h d g c g c f b e a e
h c g
