B141
      +---------
A8F16 | E9763E5D
       -A8F16
        =====
        45009E
       -4D73A6
        ======
         008575
        -B9D5AC
         ======
          42C85D
         -4D73A6
          ======
           BCF9A

base: 16
letters: 0123456789ABCDEF
difficulty: medium