s/./	&!!12345678!!abcdefgh!!/g
:
s/	\(.\)\S*\(..\)\1\(..\)\S*/\2!\3/
s/\(\S\)\(\S*\)\(.\)\(.\)!\(.\)\(.\)$/\1\4 \1\5 \2\4\3!\6\5/
t
s/\S*!\S*.//g
L
d