DAB0
      +---------
BA8E9 | 02647D44
       -BA8E9
        =====
        ADAEDD
       -DEC032
        ======
         619304
        -6ABB69
         ======
          91C554
         -97D961
          ======
           AA71A

base: 15
letters: 0123456789ABCDE
difficulty: medium