8 4
r
aaaaaaaa
bbbbbbbb
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........
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........
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c
abc.d.ef
a.bd.e.f
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abccddef
ab.c.ef.
abbccdef
abc.d.ef
abcd.e.f
r
...d.f..
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dddffiij
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a
aabbbbcc
aaabbccc
dadcccee
daabbeee
dddfgeee
ddffgghh
fffgghhh
ffggghhh