206. Reverse Linked List java solutions

Reverse a singly linked list.

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Hint:

A linked list can be reversed either iteratively or recursively. Could you implement both?

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/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
public class Solution {
    public ListNode reverseList(ListNode head) {
        if(head == null) return null;
        ListNode newlist = new ListNode(0);
        while(head != null){
            ListNode tmp = new ListNode(head.val);
            tmp.next = newlist.next;
            newlist.next = tmp;
            head = head.next;
        }
        return newlist.next;
    }
}