@Test
public void addToCellTest() {

    Partition p = new Partition();
    p.addToCell(0, 0);
    Assert.assertEquals(1, p.size());
    Assert.assertEquals(1, p.numberOfElements());
    p.addToCell(0, 1);
    Assert.assertEquals(1, p.size());
    Assert.assertEquals(2, p.numberOfElements());
}