$/=$];$b=qr'\((??{$u})*\)';$u=qr'(??{$b})|[^\(\)]';$_=<>;0while s/^((??{$b})*)\(((??{$u})*)\)S/do{print$2;$1}/e||s/((??{$b}))((??{$b}))~/$2$1/||s/\(((??{$u})*)\)\(((??{$u})*)\)\*/($1$2)/||s/\(((??{$u})*)\)\^/$1/||s/((??{$b}))a/($1)/||s/(??{$b})!//||s/((??{$b})):/$1$1/
Note that non-ascii characters in the above source code will be escaped (such as \x9f).