what does it means ?

Question

#include<stdio.h>

int main()
{
int c=2;
(--(c*=-(c==c)))*=-(c==c);
printf("%d",c);
}

Answer 1

But compiler showed 3
I thought that logic in this way.

(--(c*=-(c==c)))*=-(c==c)
(--(c*=-(1)))*=-(1)
(--(-c))*=-(1)
(--(-2))*=-(1)
(-3)*=-(1)
3

the answer would be 3.

Answer 2

c==c is always 1, as it's a numerical representation of the boolean "true" value. So it's basically:
--(2*(-1)*(-1)) so -2 * -1 (all minuses cancel each other out).
So 2.