面试题 02.02. 返回倒数第 k 个节点 - 力扣（LeetCode）

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     struct ListNode *next;
 * };
 */


int kthToLast(struct ListNode* head, int k)
{
    struct ListNode* fastnode = head;
    struct ListNode* slownode = head;
    while(k--)
    {
        fastnode = fastnode->next;
    }
    while(fastnode)
    {
        fastnode = fastnode->next;
        slownode = slownode->next;
    }
    return slownode->val;
}