????????
      +---------
RURPC | TLCLECUE
       -RURPC
        =====
        RCLUCC
       -RPTLNT
        ======
         RTTCEU
        -RRUNFR
         ======
          REPLCE
         -REEMTL
          ======
          ??????

base: 11
letters: CEFLMNPRTUY
difficulty: medium
hints: T << M
missing: Y