C Bit Manipulation Problem

[Garee]

When I perform the calculation 25441 & 0000000011111111 the answer I recieve is puzzling. Instead of the expected 97 I instead get 577.

printf( "%d", 25441 & MASK );

The output is 577 where MASK is 0000000011111111.

I performed the bitwise addition manually to double check and the answer should definitely be 97. I must have an error somewhere.

Any help is much appreciated.

 

[tntcoder]

It's because you are mixing number bases. You are using decimal and you are wanting MASK to be in binary.

0000000011111111 base 10 = 11111111 base 10
0000000011111111 base 2 = 255 base 10

25441 AND 11111111 = 577
25441 AND 255 = 97

Does that make sense?

Try using hex as well, #define MASK 0xFF

Maybe it would help if you wrote a function to translate between bases.

 

[Garee]

It's because you are mixing number bases. You are using decimal and you are wanting MASK to be in binary.

Excellent - That makes perfect sense.

Thank you for your time.