sub n{pop=~/\b(9[789]|1)$/}$/="-
";print/(\*\*+
)\1/?maybe:do{s/.*
/$&^1x98/ge;my@i;push@i,@+while/\x1b/g;@@=$i=pop@i;@@=map{/^/;map"$_ $'",grep{$'!~/ $_ /&n$'-$_}@i}@@for@i;@i?grep({n$_-$i}@@)?yes:'no':empty},"
"for<>
Note that non-ascii characters in the above source code will be escaped (such as \x9f).