@Test public void test() { QuickUnion qu = new QuickUnion(10); qu.union(0, 2); qu.union(3, 5); qu.union(6, 7); qu.union(6, 5); Assert.assertTrue(qu.connected(0, 2)); Assert.assertTrue(qu.connected(3, 5)); Assert.assertTrue(qu.connected(6, 7)); Assert.assertTrue(qu.connected(5, 6)); Assert.assertTrue(qu.connected(6, 3)); Assert.assertFalse(qu.connected(0, 3)); Assert.assertFalse(qu.connected(1, 7)); Assert.assertFalse(qu.connected(8, 9)); }