[LeetCode] 876. Middle of the Linked List 链表的中间结点
Givenanon-empty,singlylinkedlistwithheadnodehead,returnamiddlenodeoflinkedlist.Iftherearetwomiddlenodes,returnthesecondmiddlenode.Example1:Input:[1,2,3,4,5]Output:Node3fromthislist(Serialization:[3,4,