题解 | #删除链表的倒数第n个节点#

/**
 * 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 head ListNode类 
 * @param n int整型 
 * @return ListNode类
 */

struct ListNode* removeNthFromEnd(struct ListNode* head, int n ) {
     if(head->next == NULL) return NULL;
    struct ListNode* fast = head;
    struct ListNode* slow = head;
    for(int i = 0; i < n; i++){
        fast = fast->next;
    }
    if(fast == NULL) return head->next;
    while(fast->next){
        slow = slow->next;
        fast = fast->next;
    }
    slow->next = slow->next->next;
    return head;
    // write code here
}