LeetCode(2)：两数相加

题干

还是太嫩了，写的时候没考虑这些情况（进位之类的），有点被示例误导了

求解

• 时间复杂度： $O(max(m, n))$
• 空间复杂度： $O(max(m, n))$

class Solution {
	public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
		ListNode l3 = new ListNode(0);
		ListNode l = l3;
		ListNode p = l1;
		ListNode q = l2;
		int sum = 0;
		int carry = 0;
		while (p != null || q != null) {
			l3.next = new ListNode(0);
			l3 = l3.next;
			int x = (p != null) ? p.val : 0;
			int y = (q != null) ? q.val : 0;
			sum = x + y + carry;
			carry = sum / 10;
			sum %= 10;
			l3.val = sum;
			if (p != null)
				p = p.next;
			if (q != null)
				q = q.next;
			sum = 0;

		}
		if (carry > 0) {
			l3.next = new ListNode(carry);
		}
		return l.next;

	}
}