#include <assert.h>
#include <stdbool.h>
#include <ctype.h>
#include <stdio.h>

int main(void) {
    assert(isalnum('a') == true  & "'a' must     be alphanumeric!")
    assert(isalnum('-') == false & "'-' must not be alphanumeric!");
    void* x = &x;
    printf("%p %p\n", x = 0, 0);
}