[LeetCode]21. Merge Two Sorted Lists

Easy

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.

2ms:

public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
ListNode fakehead = new ListNode(-1);
ListNode l3 = fakehead;
while(l1!=null&&l2!=null){
if(l1.val<l2.val){
l3.next = l1;
l3 = l3.next;
l1 = l1.next;
}else{
l3.next = l2;
l3 = l3.next;
l2 = l2.next;
}
}

if(l1!=null)
l3.next = l1;
if(l2!=null)
l3.next = l2;
return fakehead.next;
}