struct list {
		elementtype value;
		struct list *next;
	};
 
 
typedef list *element;
 
element FirstL(list *L)
{
	return(L->next);
}
 
 
element EndL(list *L)
{
	list *l;
	l=L;
	while (l->next != NULL) {
		l=l->next;
	}
	return(l);
}
 
 
element NextL(element p, list *L)
{
	if (p->next == NULL) {
		cout << "Nepostojeci element NEXT";
		exit(0);
	}
	else {
		list *l;
		l=p->next;
		return(l);
	}
}
 
 
element PreviousL(element p, list *L)
{
	list *l;
	l=L;
	while ((l->next != NULL) && (l->next != p))
		l=l->next;
	if (l->next != NULL)
		return(l);
	else {
		cout << "Nepostojeci element PREV";
		system("pause");
        exit(0);
	}
}
 
 
element LocateL(elementtype x, list *L)
{
	list *l;
	l=L;
	while ((l->next != NULL) && (l->next->value != x))
		l=l->next;
	return(l);
}
 
 
void InsertL(elementtype x, element p, list *L)
{
	list *l;
	l=new list;
	l->next=p->next;
	p->next=l;
	l->value = p->value;
	p->value = x;
 
}
 
 
void DeleteL(element p, list *L)
{
	element l;
	p=PreviousL(p,L);
     if (p->next != NULL) {
		l=p->next;
		p->next=p->next->next;
		delete l;
	}
	else {
		cout << "Nepostojeci element DELETE";
		system("pause");
		exit(0);
	}
}
 
 
elementtype RetrieveL(element p, list *L)
{
	if (p->next != NULL) {
		elementtype x;
		x=p->value;
		return(x);
	}
	else {
		cout << "Nepostojeci element RETRIVER";
		system("pause");
		exit(0);
	}
}
 
 
void DeleteAllL(list *L)
{
	element l;
	while (L->next != NULL) {
		l=L->next;
		L->next = L->next->next;
		delete l;
	}
}
 
 
void InitL(list *L)
{
	list *l;
	l = new list;
	L->next=l;
	l->next=NULL;
 
}