题解 | #合并k个已排序的链表#

# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param lists ListNode类一维数组 
# @return ListNode类
#
class Solution:
    def mergeKLists(self , lists: List[ListNode]) -> ListNode:
        # write code here
        tmp = []
        for head in lists:
            while head:
                tmp.append(head.val)
                head = head.next
        if not tmp:
            return None 
        tmp.sort()
        res = ListNode(-1)
        cur = res
        for i in range(len(tmp)):
            cur.next = ListNode(tmp[i])
            cur = cur.next
        return res.next

辅助队列法：将 ListNode 中的所有 val 取出后进行排序，随后构造一个 新的ListNode