@Override
    public int solve(ArrayList<Character> elements) throws Exception {
        return 0;
    }
@Test
    public void testSolve() throws Exception {
        Controlador controlador = new Controlador();
        ArrayList<Character> elements = new ArrayList<>();
        elements.add('1');
        elements.add('2');
        elements.add('+');
        elements.add('4');
        elements.add('*');
        elements.add('3');
        elements.add('+');

        int result = controlador.solve(elements);
        assertEquals(0, result);
    }