Xor bitwise expression

[scuzymoto]

I was given some code that uses Xor and was trying to figure out how it does what it does. I understand the whole logical comparison of true and true is false and false and false is false but false and true is true. HOWEVER, I don't quite comprehend what a bitwise comparison is... why is 104 Xor 50 = 90 ??? Could someone explain it to me. Thanks.

[PaulLewis]

Xor switches bits. If a bit is in both operands, then the result will not have that bit set. If a bit is in only one operand, then the result will have the bit set.

so, in binary: 
OOOOOOO1 XOR 
OOOOOO1O          (i.e. 1 Xor 2 in decimal)
========
OOOOOO11           =3

In your example:
O11O1OOO XOR       =104
O1O11O1O           = 90
========
OO11OO1O           = 50

Does it help? Or is it more confusing now?

Cheers

P.S> Both Megatron and I are posting help but the darn forum messes with the formatting...

[Edited by PaulLewis on 10-02-2000 at 05:55 PM]

If you understand how it manipulates the bits, then you should have no trouble understanding this.

1101000            <- 120
0110010            <- 50
-------

1011010            <- 90

When you Xor the bits of 120 and 50, you get a value of 90.

[scuzymoto]

GOTCHA! Thats makes perfect sense now. Thanks.