reverse linked list

 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
class  {
    public ListNode reverseList(ListNode head) {
        if(head==null||head.next==null)
            return head;
        LinkedList<ListNode> temp=new LinkedList<>();
        while(head!=null)
        {
        temp.add(head);
        head=head.next;
        }      
   ListNode tempNode=temp.remove(temp.size()-1);
        ListNode resultNode=tempNode;
        while(!temp.isEmpty())
        {
            tempNode.next=temp.remove(temp.size()-1);
            tempNode=tempNode.next;
        }
        tempNode.next=null;
     return resultNode;
    }
}

public class  {
    
     * @param head: n
     * @return: The new head of reversed linked list.
     */
    public ListNode reverse(ListNode head) {
        // write your code here
        if(head==null||head.next==null)
        return head;
        ListNode cur=head.next;
        
        head.next=null;
        while(cur!=null)
        {
            ListNode temp=cur.next;
            cur.next=head;
            head=cur;
            cur=temp;
        }
        return head;
    }
}