34.合并 K 个升序链表

给你一个链表数组每个链表都已经按升序排列。请你将所有链表合并到一个升序链表中返回合并后的链表。分治法class Solution(object): def merge(self,A,B): dummyListNode() curdummy while A and B: if A.valB.val: cur.nextA curA AA.next else: cur.nextB curB BB.next cur.nextA or B return dummy.next def mergeKLists(self, lists): if len(lists)1: return lists[0] if len(lists)0: return None nlen(lists) midn//2 Aself.mergeKLists(lists[0:mid]) Bself.mergeKLists(lists[mid:n]) return self.merge(A,B)