欢迎来到起遇信息学
起遇信息学正处于上线筹建阶段,以下功能已全部开放免费体验: ✅ 完整题库浏览与代码提交评测(C / C++ / Python / Java 等) ✅ 入门到进阶的系列课程试读、作业与考试 ✅ AI 提示、AI 作业分析等智能助教功能 ✅ 赛事模拟与个人能力报告 ✅ 邮箱注册开放 ⏳ 付费课程订阅与微信/支付宝支付通道 ⏳ 手机号登录,微信扫码登录、微信公众号绑定 使用中如遇任何问题,欢迎通过页面底部 **"联系我们"** 与我们沟通。
CF1941B.Rudolf and 121
Rudolf and 121
Rudolf has an array of integers, the elements are numbered from to .
In one operation, he can choose an index () and assign:
Rudolf can apply this operation any number of times. Any index can be used zero or more times.
Can he make all the elements of the array equal to zero using this operation?
Input
The first line of the input contains a single integer () — the number of test cases in the test.
The first line of each case contains a single integer () — the number of elements in the array.
The second line of each case contains integers () — the elements of the array.
It is guaranteed that the sum of the values of over all test cases does not exceed .
Output
For each test case, output "YES" if it is possible to make all the elements of the array zero using the described operations. Otherwise, output "NO".
You can output each letter in any case (lowercase or uppercase). For example, the strings "yEs", "yes", "Yes", and "YES" will be accepted as a positive answer.
Note
In the first example, the original array is , to make all its elements zero, Rudolf can act as follows:
- apply the operation at and get the array ;
- apply the operation at and get the array ;
- apply the operation at and get the array ;
- apply the operation at and get the array .
Samples
7
5
1 3 5 5 2
5
2 4 4 5 1
5
0 1 3 3 1
6
5 6 0 2 3 0
4
1 2 7 2
3
7 1 0
4
1 1 1 1
YES
NO
YES
NO
NO
NO
NO
在线编程 IDE
建议全屏模式获得最佳体验
| 进入全屏编程 | Alt+E |
| 递交评测 | Ctrl+Enter |
| 注释/取消注释 | Ctrl+/ |
| 缩放字体 | Ctrl+滚轮 |