Reverse a singly linked list.

Example:

Input: 1->2->3->4->5->NULL
Output: 5->4->3->2->1->NULL

My method

/**  * Definition for singly-linked list.  * struct ListNode {  *     int val;  *     struct ListNode *next;  * };  */ struct ListNode* reverseList(struct ListNode* head) {     struct ListNode *new, *tmp;          if (head == NULL || head->next == NULL) {         return head;     }

    /* 獲取最後一個節點並賦值給new */     tmp = head;     while (tmp->next) {         tmp = tmp->next;     }     new = tmp;     new->next = NULL;          /* 遍歷head並利用頭插法將每個節點插入到new中 */     tmp = head;     while (tmp != new) {         struct ListNode *temp = tmp;         tmp = tmp->next;//提前儲存tmp->next的地址，防止下方被覆蓋         temp->next = new->next;         new->next = temp;

    }     return new; }

Submission Detail