题目地址 (opens new window)

  • 🙂 第一次练习 2020å¹´4月14日 最开始没太懂意思,后面看了题解 (opens new window)懂了,后面自己又默写了一次。
  • 😄 第二次练习

# 栈

解题代码

public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
    if (l1 == null)
        return l2;
    if (l2 == null)
        return l1;

    Stack<Integer> stack1 = new Stack<>();
    Stack<Integer> stack2 = new Stack<>();
    while (l1 != null) {
        stack1.push(l1.val);
        l1 = l1.next;
    }
    while (l2 != null) {
        stack2.push(l2.val);
        l2 = l2.next;
    }

    ListNode head = null;
    int curry = 0;
    while (!stack1.isEmpty() || !stack2.isEmpty() || curry > 0) {
        int sum = curry;
        sum += stack1.isEmpty() ? 0 : stack1.pop();
        sum += stack2.isEmpty() ? 0 : stack2.pop();
        ListNode node = new ListNode(sum % 10);
        node.next = head;
        head = node;
        curry = sum / 10;
    }
    return head;
}

# 易错点

  • 易错项 1
最后编辑时间: 7/14/2020, 9:21:47 AM