@Test
public void testPageHelper() {

    int n1 = 12, n2 = 14, m = 4;
    System.out.println("n1: " + n1 + ", m: " + m + ", result: " + DataUtil.pageHelper(n1, m));
    System.out.println("n2: " + n1 + ", m: " + m + ", result: " + DataUtil.pageHelper(n2, m));
}