@Test
  public void test2() { // Test case 2

    int output = cr.rem(2, 0);
    assertEquals("", -1, output);
  }
  @Test
  public void test3() { // Test case 3

    int output = cr.rem(100, 3);
    assertEquals("", 1, output);
  }
  @Test
  public void test1() { // Test case 1

    int output = cr.rem(2, 1);
    assertEquals("", 0, output);
  }