HHH
      +---------
MHAHJ | MHACJHAR
       -MCMQGJ
        ======
         MRRHHA
        -MCMQGJ
         ======
          MCMRAR
         -MCMQGJ
          ======
             AGR

base: 9
letters: ACGHJMPQR
missing: P
difficulty: intermediate
restrictions: no multiplication