public boolean contains(int id) {
        checkIdInRange(id);
        return positions[id] != NOT_PRESENT;
    }
@Test
    void testContains() {
        create(4);
        push(1, 0.1f);
        push(2, 0.7f);
        push(0, 0.5f);
        assertFalse(contains(3));
        assertTrue(contains(1));
        assertEquals(1, poll());
        assertFalse(contains(1));
    }