构造链表结点数组,遍历一遍,直接提取数组即可
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
ListNode* findKthToTail(ListNode* pListHead, int k) {
vector<ListNode*> a;
while(pListHead){
a.push_back(pListHead);
pListHead=pListHead->next;
}
if(k>a.size())return NULL;
else return a[a.size()-k];
}
};