// List1.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <iostream>

using namespace std;
struct list
{
	int inf;
	list*next;
};
void init(list**begin,list**end, int n);
void output(list*begin);
void add_begin(list**begin, int n);
void add_end(list**begin, int n);
void add_prev(list**begin, int n, int x);
void add_next(list**begin, int n, int x);
int main()
{
	list*begin = NULL, *end = NULL;
	int n, k, el, x;
	do
	{
		cout << "n = ";
		cin >> n;
		init(&begin, &end, n);
		cout << "Next ? ";
		cin >> k;
	} while (k != 0);
	cout << "el = ";
	cin >> el;
	add_begin(&begin, el);
	cout << "el = ";
	cin >> el;
	add_end(&begin, el);
	cout << "el = ";
	cin >> el;
	cout << "x = ";
	cin >> x;
	add_prev(&begin, el, x);
	cout << "el = ";
	cin >> el;
	cout << "x = ";
	cin >> x;
	add_next(&begin, el, x);
	cout << "List: ";
	output(begin);
	system("pause");
    return 0;
}
void init(list**begin, list**end, int n)
{
	list*t = new list;
	if (*begin == NULL)
	{
		t->inf = n;
		t->next = NULL;
		*begin = *end = t;
	}
	else
	{
		t->inf = n;
		t->next = NULL;
		(*end)->next = t;
		*end = t;
	}
}
void output(list*begin)
{
	list*t = new list;
	t = begin;
	while (t != NULL)
	{
		cout << t->inf << " ";
		t = t->next;
	}
	cout << endl;
}
void add_begin(list**begin, int n)
{
	list*t = new list;
	t->inf = n;
	t->next = *begin;
	*begin = t;
}
void add_end(list**begin, int n)
{
	list*t = new list;
	t = *begin;
	while (t != NULL)
	{
		t = t->next;
	}
	list*a = new list;
	a->next = NULL;
	a->inf = n;
	t->next = a;
}
void add_prev(list**begin, int n, int x)
{

}
void add_next(list**begin, int n, int x)
{

}