【剑指offer】链表中倒数第k个结点

 1 /*
 2 struct ListNode {
 3     int val;
 4     struct ListNode *next;
 5     ListNode(int x) :
 6             val(x), next(NULL) {
 7     }
 8 };*/
 9 class Solution {
10 public:
11     ListNode* FindKthToTail(ListNode* pListHead, unsigned int k) {
12         if(pListHead == NULL || k == 0)    return NULL;
13         ListNode* pre = pListHead;
14         ListNode* lst = pListHead;
15         while(k > 0){
16             if(!pre)    return NULL;
17             pre = pre->next;
18             k--;
19         }
20         while(pre!=NULL){
21             pre = pre->next;
22             lst = lst->next;
23         }
24         return lst;
25     }
26 };