sub bowl {
  $_=pop;                                          #  7

  m#(./(?=(.)(?{$_.=$2}))|X(?=(..)(?{$_.=$3}))|..){9}#;
                                                   # 53
  s#./|X#55#g;                                     # 12
  s/\B/+/g;                                        #  9
  eval                                             #  4
}
#                                                   ___
#                                                    85