D34F
      +---------
37F5C | 8EB8F3C9
       -37F5C
        =====
        764573
       -7C3694
        ======
         03B3AC
        -0B2D3E
         ======
          CF0D09
         -CB15D8
          ======
           DFBFD

base: 16
letters: 0123456789ABCDEF
difficulty: hard