@Test
    public void smallInsertTest(){
        Fibonacci Fiheap = new Fibonacci();
        for (int i = 4; i != 0; i--) {
            Fiheap.insert(i);
        }
        Fibonacci Fiheap2 = new Fibonacci();
        for (int j = 4; j != 0; j--) {
            Fiheap2.insert(j);
        }
        
        Fibonacci union = Fiheap.union(Fiheap, Fiheap2);
        assertEquals(union.extract_min().value, 1);
        assertEquals(union.extract_min().value, 1);
        assertEquals(union.extract_min().value, 2);
        assertEquals(union.extract_min().value, 2);

    }