二刷hot100-160.相交链表

非常巧妙，先让指针分别循环两个链表，到结尾时在2指向对方链表继续循环，当指针指向同一结点，就是相交节点；

/** * Definition for singly-linked list. * public class ListNode { * int val; * ListNode next; * ListNode(int x) { * val = x; * next = null; * } * } */ public class Solution { public ListNode getIntersectionNode(ListNode headA, ListNode headB) { ListNode A = headA; ListNode B = headB; while(A != B){ A = A == null ? headB : A.next; B = B == null ? headA : B.next; } return A; } }