Check if integer is 0 with two restricted operations

Question

I am trying to write a function isZero(int x) that returns 1 if x is 0, and returns 0 otherwise. How can I only do this with two of the following operators?

! ~ & ^ | + << >>

Answer 1

What about !!!x?

Look at following diagram for values zero and different than zero:

      x == 0 | x <> 0
      -------+-------
!x         1 |      0
!!x        0 |      1
!!!x       1 |      0

Isn't that what you want?