04A1
      +---------
07B89 | 80C2A169
       -90497
        =====
        B63751
       -7892B1
        ======
         713066
        -75135B
         ======
          798189
         -744108
          ======
           70618

base: 13
letters: 0123456789ABC
difficulty: medium
restrictions: no multiplication