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s/. //
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s/./;&9876543210/g
s/;\(.\)[^;]*\1/;/g
t
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s/\([^;]*\);/\1\1\1\1\1\1\1\1\1\1/
t
G
s/\n\(.\).*/\
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t1
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s/\(.\)
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t1
s/..//
G
s/\n. [^ ]* /
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t2
:2
s/.\(
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t2
s/
\|//g