程式語言 - LeetCode - C - 206. Reverse Linked List



參考資訊:
https://www.cnblogs.com/cnoodle/p/11670754.html

題目:


解答:

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     struct ListNode *next;
 * };
 */
struct ListNode* reverseList(struct ListNode *head)
{
    struct ListNode *pre = NULL;
    struct ListNode *next = NULL;

    if ((head == NULL) || (head->next == NULL)) {
        return head;
    }

    while (head) {
        next = head->next;
        head->next = pre;

        pre = head;
        head = next;
    }

    return pre;
}