????????
      +---------
MQCXQ | CCPLLMHR
       -MQCXQ
        =====
         PEHCM
        -HMQHJ
         =====
         MQCEMH
        -MCPLQL
         ======
          MRPHMR
         -MCPLQL
          ======
          ??????

base: 10
letters: CEHJLMPQRX
difficulty: easy