第一版:.完整的代码包括输入输出 #链表中结束后记得返回一个指向头结点的指针 # Definition for singly-linked list. class ListNode: def __init__(self, x): self.val = x self.next = None class LinkList: def __init__(self): self.head=None def initList(self, data): # 创建头结点 self.head = ListNode(data[0]) r=self.head p = self.head # 逐个为 data 内的数据创建结点, 建立链表 for i in data[1:]: node = ListNode(i) p.next = node p = p.next return r def printlist(self,head): if head == None: return node = head while node != None: print(node.val,end=' ') node = node.next class Solution: def mergeTwoLists(self, l1, l2): """ :type l1: ListNode :type l2: ListNode :rtype: ListNode """ head = ListNode(0) first = head while l1!=None and l2!=None: if l1.val <= l2.val: