I have code in one of the source file as follows:

#include <stdio.h>
#include <math.h>

int a ;
int b = 256 ;
int c = 16 ;
int d = 4 ;

int main() {

    if ((d <= (b) && (d == ( c / sizeof(a))))
    {
        printf("%d",sizeof(a) );
    }
    return 0;

} 

I have removed the casts and have simplified on the data names. The sizeof(a) can be taken as 4. I want to know if the the if syntax is a valid one and if so why doesn't it execute?

PS : I haven't sat down on this for long due to time constraints. Pardon me if you find a childish error in the code.