#include <stdio.h>

int main() {
    //print adr of pt: printf("%p", (void*)p);
    int a = 1;
    int *ptr;
    ptr = &a;

    printf("a: %d, p: %p\n", a, (void*)ptr);

    //change val: long
    long n1 = 0L;
    long n2 = 0L;
    long *p = NULL;

    p = &n1;
    *p = 2L;
    ++n2;
    n2 += *p;
    p = &n2;
    ++*p;
    printf("%ld, %ld, %ld, %ld", n1, n2, *p, *p + n2);


    return 0;
}