C++ 代码
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
ListNode *findFirstCommonNode(ListNode *headA, ListNode *headB) {
auto p1=headA;
auto p2=headB;
while(p1 != p2)
{
if(p1 != nullptr)
p1=p1->next;
else p1=headB;
if(p2 != nullptr)
p2=p2->next;
else p2=headA;
}
return p1;
}
};