@classmethod
    def merge(cls, l1, l2):
        # l1.init_list([1, 5, 7, 9, 10])
        # l2.init_list([2, 4, 8, 14])
        # 将 l2 合并到l1中
        p = l1.head
        q = l2.head.next
        while p.next is not None:
            print(p.next.value,q.value)
            if p.next.value>q.value:
                t = p.next
                p.next = q
                p = p.next
                q = t
            else:
                p = p.next
        p.next = q
        return l1