题解 | #链表中倒数第k个结点#

/**
 * struct ListNode {
 *	int val;
 *	struct ListNode *next;
 * };
 */

/**
 * 
 * @param pListHead ListNode类 
 * @param k int整型 
 * @return ListNode类
 */
struct ListNode* FindKthToTail(struct ListNode* pListHead, int k )
{
    //思路一，要找倒数第k个，那就是找正数第n-k+1个,先求出链表长度，减去k再加一
    int n = 0;
    int m = 0;
    if (pListHead == NULL)
        return NULL;
    struct ListNode* cur = pListHead;
    while (cur)
    {
        n++;
        cur = cur->next;
    }
    m = n - k + 1;
    cur = NULL;
    if (m > 0)
    {
        cur = pListHead;
        while (--m)
        {
            cur = cur->next;
        }
    }
    return cur;
}