題目

反轉一個單鏈表。

示例:

輸入: 1->2->3->4->5->NULL
輸出: 5->4->3->2->1->NULL

程式碼

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
class Solution {
    public ListNode reverseList(ListNode head) {
        if(head==null || head.next==null)
            return head;
        ListNode node = new ListNode(head.val);  
        ListNode temp = null;
        head = head.next;
        while(head!=null)
        {
            temp = new ListNode(head.val);
            temp.next = node;
            node = temp;
            head = head.next;
        }
        return node;
    }
}