题解 | #反转链表#

#include<iostream>


class Solution {
public:
    /**
     * 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 
     * @return ListNode类
     */
    ListNode* ReverseList(ListNode* head) {
        if(head == nullptr || head->next == nullptr)
            return head;
        ListNode dummy = ListNode(0);
        dummy.next = head;
        ListNode *pre=head, *cur=head->next;
        while(cur !=nullptr) {
            ListNode* nxt = cur->next;
            pre->next = nxt;
            cur->next = dummy.next;
            dummy.next = cur;
            cur = nxt;
            nxt = nxt->next;
        }
        return dummy.next;
    }
};