[Leetcode] Merge Two Sorted Lists

public class Solution {
public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
ListNode dummy1 = new ListNode(0), dummy2 = new ListNode(0), dummy3 = new ListNode(0), tail = dummy3;
dummy1.next = l1;
dummy2.next = l2;
dummy3.next = null;
while(l1 != null && l2 != null) {
ListNode minNode = l1.val < l2.val ? l1 : l2;
ListNode minDummy = l1.val < l2.val ? dummy1 : dummy2;
minDummy.next = minNode.next;
l1 = minNode == l1 ? l1.next : l1;
l2 = minNode == l2 ? l2.next : l2;
minNode.next = null;
tail.next = minNode;
tail = tail.next;
}

tail.next = l1 == null ? l2 : l1;

return dummy3.next;
}
}