COMPLEJIDAD GETPOS

                                                                     //O(n)
    private NodoD<T> getPos(int i)throws ExceptionUFPS{                         //T=4+max(c1,4+1+E(1+2+2)+1)
        if(i<0||i>=this.tamanio){                                               //4
            throw new ExceptionUFPS("El índice solicitado no existe en la Lista Doble");//T(Exception)
        }
        else    
        {
            NodoD<T> t=this.cabeza.getSig();                                    //4
            while(i>0){                                                         //1+E(1)
                t=t.getSig();                                                   //2
                i--;                                                            //2
            }        
            return(t);                                                          //1
        }
     
    }

T = 4+max(c1,4+1+1n+2n+2n+1)

T = 4+6+5n = 10+5n = n

O(n)