bit manipulation - C Programming - XOR Bitwise Operation

Question

What operation does the following ‘C’ statement perform?

star = star ^ 0b00100100;

(A) Toggles bits 2 and 5 of the variable star.

(B) Clears all bits except bits 2 and 5 of the variable star.

(C) Sets all bits except bits 2 and 5 of the variable star.

(D) Multiplies value in the variable star with 0b00100100.

I'm still clueless about this. Can someone help me out?

Answer 1

XOR operator (also called "logical addition") is defined like this:

a   b   a^b
-----------
0   0    0
0   1    1
1   0    1
1   1    0

So a^0 leaves a intact while a^1 toggles it.

For multiple-bit values, the operation is performed bitwise, i.e. between corresponding bits of the operands.