#include <bits/stdc++.h>
#include <gtest/gtest.h>

using namespace std;

class Node {
public:
    Node(int i)
        : val(i), 
          prev(nullptr),
          next(nullptr),
          child(nullptr)
    {}
        
    int val;
    Node* prev;
    Node* next;
    Node* child;
};

int main(void)
{
    Node * _1 = new Node( 1);
    Node * _2 = new Node( 2);  _2->prev=_1; _1->next=_2;
    Node * _3 = new Node( 3);  _3->prev=_2; _2->next=_3;    
    Node * _4 = new Node( 4);  _4->prev=_3; _3->next=_4;
    Node * _5 = new Node( 5);  _5->prev=_4; _4->next=_5;    
    Node * _6 = new Node( 6);  _6->prev=_5; _5->next=_6;    

    Node * _7 = new Node( 7);  _2->child=_7;
    Node * _8 = new Node( 8);  _8->prev =_7; _7->next=_8;
    Node * _9 = new Node( 9);  _9->prev =_8; _8->next=_9;
    Node *_10 = new Node(10); _10->prev =_9; _9->next=_10;    

    Node *_11 = new Node(11);  _8->child=_11;
    Node *_12 = new Node(12); _12->prev =_11; _11->next=_12;

    Node *head = _1;

    auto printListRecursive = [](Node* node, auto&& printListRecursive)
    {
        if (node == nullptr)
            return;            

        cout << node->val << " ";

        return printListRecursive(node->next, printListRecursive);
    };

    auto printList = [](Node* node)
    {
        while (node != nullptr)
        {
            cout << node->val << " ";
            node = node->next;
        }
        cout << endl;        
    };

    printListRecursive(head, printListRecursive);
    cout << endl;

    printList(head);

    cout << std::hardware_destructive_interference_size << endl;
    
    return 0;
}