LeetCode-merge-two-sorted-lists

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) {
 *         val = x;
 *         next = null;
 *     }
 * }
 */
public class Solution {
    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
        ListNode node = new ListNode(0);
        ListNode root = node;
        ListNode node1 = l1;
        ListNode node2 = l2;
         
        while(l1!=null&&l2!=null){
            ListNode nextNode = new ListNode(0);
            if(l1.val<=l2.val){
               root.next = l1;
                l1=l1.next;
            }else{
                root.next = l2;
                l2=l2.next;
            }
            root=root.next;
        }
        if(l1!=null){
          root.next = l1;        }
        if(l2!=null){
            root.next = l2;        }
        return node.next;
    }
}