DF0F
      +---------
D195D | B1A7F2A2
       -03007
        =====
        D8CFE2
       -DAD18B
        ======
         A8065A
        -A6C9B5
         ======
          DA7382
         -DAD18B
          ======
            10F5

base: 16
letters: 0123456789ABCDEF
difficulty: hard
missing: 4