algorithm - binary opposite number -

I want to get the opposite number of the binary number (x -> - (x) and - (x) - & Gt; x).

What will be the algorithms? I think change all the bits ("1" to "0" and "0" to "1") and add "1" for it is it okay?

thnx

Your algorithm is correct for two complementary numbers:

  -x = ~ X   
 and for sign-magnitude numbers:  
  -x = x ^ (1  < / Pre> 
 where the sign bit is offset in the word  n  I am using C operator notation -  ^  is a bitwast exclusive or operator, and  & Lt; & Lt;  is a left shift.  
 Representing the second number, you have to use some other operation.