两个链表的第一个公共结点

public class Solution {
    public ListNode FindFirstCommonNode(ListNode pHead1, ListNode pHead2) {
        ListNode tmp1=pHead1;
        ListNode tmp2=pHead2;
        while(pHead1!=null&&pHead2!=null){
            ListNode cur=tmp1;
            if(tmp1.val!=tmp2.val){
                tmp1=tmp1.next;
                tmp2=tmp2.next;
            }
            return cur;
        }
        if(pHead1!=null){
            return pHead1;
        }
        if(pHead2!=null){
            return pHead2;
        }
    }
}

public class Solution {
    public ListNode FindFirstCommonNode(ListNode pHead1, ListNode pHead2) {
        ListNode l1 = pHead1, l2 = pHead2;
        while(l1 != l2){
            l1 = (l1==null)?pHead2:l1.next;
            l2 = (l2==null)?pHead1:l2.next;
        }
        return l1;
    }
}