public void LeetCode2Test(ListNode a, ListNode b, ListNode c)
{
var d = new LeetCode2().AddTwoNumbers(a, b);
while (c != null && d != null)
{
Assert.Equal(c.val, d.val);
c = c.next;
d = d.next;
}
Assert.True(c == null && d == null);
}
