????????
      +---------
YCTJY | CUYHYYPT
       -YCTJY
        =====
        PHTHJY
       -PPFJPJ
        ======
         PPPGYP
        - UJYJT
         ======
          YPFHCT
         -YPPYHT
          ======
           ?????

base: 9
letters: CFGHJPTUY
difficulty: intermediate