题解 | #反转链表#

/**
 * 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
 * @return ListNode类
 */
struct ListNode* ReverseList(struct ListNode* head ) {
    // write code here
    struct ListNode* prev = NULL;
    struct ListNode* next = NULL;
    while (head != NULL) {
        next = head->next;
        head->next = prev;
        prev = head;
        head = next;
    }
    return prev;
}