题解 | 链表中倒数最后k个结点

/**
 * struct ListNode {
 *	int val;
 *	struct ListNode *next;
 * };
 */
/**
 * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
 *
 * 
 * @param pHead ListNode类 
 * @param k int整型 
 * @return ListNode类
 */
struct ListNode* FindKthToTail(struct ListNode* pHead, int k ) {
    // write code here
    struct ListNode *fastpointer=pHead,*slowpointer=pHead,*cur=pHead;
    int count=0;
while(cur!=NULL)
{
    cur=cur->next;
    count++;
}
if(count<k)
return NULL;
    while(k>0)
    {
fastpointer=fastpointer->next;
        k--;
    }
    while(fastpointer!=NULL)
    {
        fastpointer=fastpointer->next;
        slowpointer=slowpointer->next;
    }
    return slowpointer;
}