问题描述
给你单链表的头节点 head ，请你反转链表，并返回反转后的链表。
解答代码
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* struct ListNode *next;
* };
*/
struct ListNode* reverseList(struct ListNode* head){
struct ListNode *pre = NULL, *cur = head, *next = NULL;
while (cur) {
next = cur->next;
cur->next = pre;
pre = cur;
cur = next;
}
return pre;
}