#include <iostream>

using namespace std;

class ListElement
{
private:
	int key;
	ListElement* next;
public:
	ListElement(int key, ListElement* next)
	{
		this->key = key;
		this->next = next;
	}
	int getKey()
	{
		return key;
	}
	ListElement* getNext()
	{
		return next;
	}
};

int main()
{
	ListElement* firstElement = new ListElement(0, NULL);
	ListElement* secondElement = new ListElement(5, firstElement);
	ListElement* thirdElement = new ListElement(7, secondElement);
	ListElement* fourthElement = new ListElement(3, thirdElement);

	cout << fourthElement->getKey() << "\n";
	cout << fourthElement->getNext()->getKey() << "\n";
	cout << fourthElement->getNext()->getNext()->getKey() << "\n";
	cout << fourthElement->getNext()->getNext()->getNext()->getKey() << "\n";
	return 0;
}