/*
public class ListNode {
    int val;
    ListNode next = null;

    ListNode(int val) {
        this.val = val;
    }
}*/
public class Solution {
    public ListNode ReverseList(ListNode head) {
       
        if(head==null){
            return null;
        }
        if(head.next==null){
            return head;
        }
        ListNode cur =head.next;
        ListNode curNext=cur.next;
        ListNode h=head;
         h.next=null;
        while(cur!=null){
            curNext=cur.next;
            cur.next=h;
           
            h=cur;
            cur=curNext;
        }
        return h;
    }
}