struct ListNode reversestruct ListNode head struct ListNode prev = NULL; struct ListNode curr = head; while curr != NULL struct ListNode next = curr-next; curr-next = prev;

struct ListNode *reverse(struct ListNode *head) { // 创建两个指针，prev指向前一个节点，curr指向当前节点 struct ListNode *prev = NULL; struct ListNode *curr = head;

// 循环遍历链表，直到curr指向最后一个节点
while (curr != NULL) {
    // 创建一个指针next，指向当前节点的下一个节点
    struct ListNode *next = curr->next;
    
    // 将当前节点的next指针指向前一个节点，实现反转
    curr->next = prev;
    
    // 更新prev和curr指针，分别指向当前节点和下一个节点
    prev = curr;
    curr = next;
}

// 返回反转后的链表的头节点
return prev;

}