AcWing 36. 合并两个排序的链表
class Solution {
public ListNode merge(ListNode l1, ListNode l2) {
ListNode dummy = new ListNode(0);
ListNode p = dummy;
while (l1 != null && l2 != null) {
if (l1.val < l2.val) {
p.next = l1;
l1 = l1.next;
} else {
p.next = l2;
l2 = l2.next;
}
p = p.next;
}
p.next = l1 != null ? l1 : l2;
return dummy.next;
}
}