I'm kind of puzzled by this. I thought the ~ operator in C++ was supposed to work differently (not so Matlab-y). Here's a minimum working example:
#include <iostream>
using namespace std;
int main(int argc, char **argv)
{
bool banana = true;
bool peach = false;
cout << banana << ~banana << endl;
cout << peach << ~peach << endl;
}
And here's my output:
1-2
0-1
I hope someone will have some insight into this.
This is exactly what should happen: when you invert the binary representation of zero, you get negative one; when you invert binary representation of one, you get negative two in two's complement representation.
00000000 --> ~ --> 11111111 // This is -1
00000001 --> ~ --> 11111110 // This is -2
Note that even though you start with a bool
, operator ~
causes the value to be promoted to an int
by the rules of integer promotions. If you need to invert a bool
to a bool
, use operator !
instead of ~
.
~ is bitwise NOT operator which means it flips all the bits. For boolean NOT, you should be using ! operator