????????
      ----------
JJMUL ) HYHMFFTQ
       -YHJJG
        =====
        NTRUTF
       -NRTLGX
        ======
         QMTJJT
        -QLYYTY
         ======
          XWUUNQ
         -QTQGPP
          ======
          ??????

base: 15
symbols: FGHJLMNPQRTUWXY
difficulty: medium