???????
     +--------
5283 | 9A5A186
      -8532
       ====
       50971
      -5023A
       =====
         2498
        -2A17
         ====
          3976
         -A734
          ====
          ????

base: 11
letters: 0123456789A
difficulty: medium
hints: 8 << 7, 4 << 7