Leetcode, Add Two Numbers, Programming, Leetcode Medium, Java.
0; int y = (l2 != null) ? l2.val : 0; int sum = carry + x + y; carry = sum / 10; current.next = new ListNode(sum % 10); current = current.next; if (l1 != null) l1 = l1.next; if (l2 != null) l2 = l2.next; } if (carry > 0) { current.next = new ListNode(carry); } return dummy.next; } } Time and Space