38A9
      +---------
3570F | C9217E0F
       -CC9BD
        =====
         FC97E
        -FD98F
         =====
          CD6A0
         -3570F
          =====
          3C659F
         -3CE41D
          ======
            888F

base: 16
letters: 0123456789ABCDEF
difficulty: medium