Secret Number

Score: 61.00 (pass)

#!/usr/bin/perl -l
$_=pop;print,s/.(?=(.))/"$&$1"%9or$1&&9/eg,chop while"0$_"

Score: 68.00 (pass)

#!/usr/bin/perl -l
$_=pop;print,s/.(?=0|(.))/($x=$&.$1)--&&$x%9+1/eg,chop while"0$_"