ERG
      +---------
CEFFP | CFQEFXQC
       -CFCFQG
        ======
          WQXRQ
         -CEFFP
          =====
           PXFEC
          -QNFRE
           =====
           RJFNT

base: 12
letters: CEFGJNPQRTWX
difficulty: intermediate
restrictions: no multiplication