typedef struct _stack {
	char* data;
	int capacity;
	int size;
}* Stack;

typedef struct Element
{
	struct Element *prev;
	Stack sir;
	struct Element *next;
}Element;



typedef struct Element* Lista;

Lista addLast(Lista l, Stack val)
{
        Lista nou, temp;
        if (l==NULL)
        {
                l->prev = NULL;
                l->sir = val;
                l->next = NULL;
        }
        else
        {
                nou=(Element *)malloc(sizeof(Element));
                temp=l;
                while(temp->next!=NULL)
                        temp=temp->next;
                nou->sir=val;
                nou->next=NULL;
                nou->prev=temp;
                temp->next=nou;
        }
        return l;
}