Merge K sorted link list
还是昨天的合并 K 个有序链表,今天去社区看了下,还有更简单的解决方案,时间复杂度和空间复杂度更好,大概的思路是用python的最小堆来实现,每次从堆里弹出最小元素,然后最近一次哪个链表出了最小元素就把下一个塞进堆里,很高效,很简洁,元祖(tuple)的运用是这个实现的点睛之笔,下面贴出代码
def mergeKLists(self, lists): from heap import heappop, heapify, heapreplace dummy = node = ListNode(0) # 下面这一步很赞 h = [(n.val), n] for n in lists if n] # n 转 minheap heapify(h) while(h): # 取 堆里最小的值 v, n = h[0] if n.next is None: heappop(h) else: # 弹出最小值,并把同一链表的下一个最小值放进堆中 heapreplace(h, (n.next.val, n.next)) node.next = n node = node.next return dummy.next复制代码
Conclusion
想起了大佬 Linus 的那句话
"Bad programmers worry about the code. Good programmers worry about data structures and their relationships."