#include <stdio.h>
#include <string.h>
#include <stdlib.h>

struct node{
    int key;
    int data;
    struct node *next;
};

int main(void) {
struct node *link = (struct node*) malloc(sizeof(struct node));
link->key = 10;
link->data = 100;
link->next = link;
printf("%zd %zd %zd %zd\n", sizeof(link->key), sizeof(link->data), sizeof(link->next), sizeof(*link));

return 0;
}