public static void main(String[] args) {
        items = new ArrayList<>();
        int op;
        
        do{
            System.out.println("1-AGREGAR");
            System.out.println("2-RENTAR");
            System.out.println("3-LISTAR");
            System.out.println("4-EVALUAR ESTADO");
            System.out.println("5-DEVOLVER COPIAS");
            System.out.println("6-SALIR");
            System.out.print("Escoja Opcion: ");
            op = lea.nextInt();
            
            switch(op){
                case 1:
                    addItem();
                    break;
                case 2:
                    rentItem();
                    break;
                case 3:
                    list();
                    break;
                case 4:
                    evaluate();
                    break;
                case 5:
                    returnItems();
                    break;
            }
        }while(op!=6);
    }