双指针进行遍历
import java.util.*; /* public class ListNode { int val; ListNode next = null; ListNode(int val) { this.val = val; } }*/ public class Solution { public ListNode FindFirstCommonNode(ListNode pHead1, ListNode pHead2) { ListNode l1=pHead1; ListNode l2=pHead2; while(l1!=l2){ l1=l1==null?pHead1:l1.next; l2=l2==null?pHead2:l2.next; } return l1; } }