#include <iostream>
#include <stdio.h>
#include <stdlib.h>
using namespace std;

struct n {
    int x;
    n * next;
};

typedef n node;

int main ()
{
    node * root;
    root = (node *)malloc(sizeof(node));
    node * iter;
    iter = root;
    iter->x = 10;
    iter->next = (node *)malloc(sizeof(node));
    iter->next->x = 20;
    iter->next->next = (node *)malloc(sizeof(node));
    iter->next->next->x = 30;
    cout<<iter->x<<endl;
    iter = iter->next;
    cout<<iter->x<<endl;
    iter = iter->next;
    cout<<iter->x<<endl;
};