What is stupid about it?

Boolean AND Logic Table:

Code:

1 & 1 = 1
0 & 1 = 0
1 & 0 = 0
0 & 0 = 0


Therefore:

Code:

 1111d = 10001010111b
 0016d = 00000010000b
&--------------------&
         00000010000b = 0016d


-genius_at_work