算法14~19中，la、lb、Ic为各个单链表的头指针
算法14~19中，la、lb、Ic为各个单链表的头指针，直接用头指针表示和操作单链表。17·设计算法，将两个递增有序单链表la和lb合并成一个递减有序表。
答案
class LNode: def __init__(self,data): self.data=data self.next=None class LinkList: def __init__(self): self.head = LNode(None) def merge_list(la:LinkList, lb:LinkList) -> LinkList: pa = la.head.next pb = lb.head.next lc = la pc = lc.head while pa and pb: if pa.data <= pb.data: pc.next = pa pc = pa pa = pa.next else: pc.next = pb pc = pb pb = pb.next pc.next = pa if pa else pb return lc