@Test
    public void test09(){
        String str = "12345678";
        char[] charArray = str.toCharArray();
        char[] chars = new char[str.length()];
        for (int i = charArray.length -1,k = 0; i >= 0; i--,k++) {
            chars[k] = charArray[i];
        }
        String s = String.valueOf(chars);
        System.out.println(s);
    }