LeetCode 23 合并K个排序链表

合并 k 个排序链表，返回合并后的排序链表。请分析和描述算法的复杂度。

 

输入：1->4->5, 1->3->4, 2->6

输出：1->1->2->3->4->4->5->6

 

python3：

class Solution:
    def mergeKLists(self, lists: List[ListNode]) -> ListNode:
        if not lists:return
        n = len(lists)
        return self.merge(lists, 0, n - 1)
    

    def merge(self, lists, left, right):
        if left == right:
            return lists[left]
        mid = left + (right - left) // 2
        l1 = self.merge(lists, left, mid)
        l2 = self.merge(lists, mid + 1, right)
        return self.mergeTwoLists(l1, l2)
    

    def mergeTwoLists(self, l1, l2):
        if not l1:return l2
        if not l2:return l1
        if l1.val < l2.val:
            l1.next = self.mergeTwoLists(l1.next, l2)
            return l1
        else:
            l2.next = self.mergeTwoLists(l1, l2.next)
            return l2

 

来源：CSDN

作者：-TOXNO-

链接：https://blog.csdn.net/qq_36911138/article/details/104219877