void sterge(nod *&p)
{
    nod *q,*r;
    while(p->info%2==0&&p!=NULL)
    {
        q=p;
        p=p->urm;
        delete q;
    }
    if(p!=NULL)
    {
        q=p;
        while(q->urm!=NULL)
            if(q->urm->info%2==0)
        {
            r=q->urm;
            q->urm=r->urm;
            delete r;
        }
        else
            q=q->urm;
    }