题解 | 返回链表中倒数第K个结点

典型的快慢指针问题

struct ListNode* FindKthToTail(struct ListNode* pListHead, int k ) {
    // write code here
    struct ListNode* fast=pListHead;
    struct ListNode* slow =pListHead;
    while(k--)
    {
         if(fast==NULL)
        {
            return NULL;
        }
        fast=fast->next;
       }
    while(fast)
    {
        fast=fast->next;
        slow=slow->next;
    }
    return slow;
}