题解 | #两个链表的第一个公共结点#
两个链表的第一个公共结点
https://www.nowcoder.com/practice/6ab1d9a29e88450685099d45c9e31e46
/*
struct ListNode {
int val;
struct ListNode *next;
ListNode(int x) :
val(x), next(NULL) {
}
};*/
class Solution {
public:
ListNode* FindFirstCommonNode( ListNode* pHead1, ListNode* pHead2) {
unordered_set<ListNode*> visited;
while(pHead1)
{
visited.insert(pHead1);
pHead1=pHead1->next;
}
while(pHead2)
{
if(visited.count(pHead2))
return pHead2;
pHead2=pHead2->next;
}
return nullptr;
}
};
