F90B
      +---------
0B14C | A2F18BE1
       -A9E54
        =====
         1D1AB
        -1AB47
         =====
          9C54E
         -9F5D3
          =====
           F6D81
          -0B14C
           =====
           B30AB

base: 16
letters: 0123456789ABCDEF
difficulty: hard