HJMTU
     +---------
RCRT | MGGFQQHR
      -TCTF
       ====
       RTMGQ
      -RHMFM
       =====
         JURQ
        -JGUT
         ====
          QHHH
         -MGCM
          ====
          RFQQR
         -RFRRF
          =====
            MCJ

base: 10
letters: CFGHJMQRTU
difficulty: intermediate
restrictions: no multiplication