Question
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.
Example:
Input: 1->2->4, 1->3->4
Output: 1->1->2->3->4->4
Solution
TODO
Code
class Solution {
public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
if(l1 == null) return l2;
if(l2 == null) return l1;
ListNode dummyHead = new ListNode(0);
ListNode tail = dummyHead;
while(l1 != null || l2 != null) {
boolean selectL1 = true;
if(l1 == null || l2 != null && l1.val > l2.val) selectL1 = false;
if(selectL1) {
tail.next = l1;
l1 = l1.next;
}
else {
tail.next = l2;
l2 = l2.next;
}
tail = tail.next;
}
return dummyHead.next;
}
}
Performance
TODO