2601
      +---------
2F1D6 | 66CEF659
       -2F1D6
        =====
         83C56
        -15EF8
         =====
          C09F5
         -C23AB
          =====
           D6459
          -4774E
           =====
           2D3DD

base: 16
letters: 0123456789ABCDEF
difficulty: medium