#include <iostream>
using namespace std;
struct nod
{
    int val;
    nod *urm;
}*p=NULL,*q=NULL;
void afisare(nod *& p)
{
    nod *r;
    r=p;
    while(r!=NULL)
    {
        cout<<r->val<<" ";
        r=r->urm;
    }
    cout<<endl;
}
void stergere(nod *& p)
{
    nod *r;
    r=p;
    p=p->urm;
    delete r;
}
void adaugare(nod *& p,nod *& q,int nr)
{
    if(p==NULL)
    {
        nod *r;
        r=new(nod);
        r->val=nr;
        r->urm=NULL;
        p=r;
        q=r;
    }
    else
    {
        nod *r;
        r=new(nod);
        r->val=nr;
        r->urm=NULL;
        q->urm=r;
        q=r;
    }
}
int main()
{
    adaugare(p,q,1);
    adaugare(p,q,2);
    adaugare(p,q,3);
    stergere(p);
    adaugare(p,q,4);
    adaugare(p,q,5);
    adaugare(p,q,6);
    stergere(p);
    stergere(p);
    afisare(p);
    return 0;
}