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。
CF1559A.Mocha and Math
Mocha and Math
Mocha is a young girl from high school. She has learned so much interesting knowledge from her teachers, especially her math teacher. Recently, Mocha is learning about binary system and very interested in bitwise operation.
This day, Mocha got a sequence of length . In each operation, she can select an arbitrary interval and for all values (), replace with at the same time, where denotes the bitwise AND operation. This operation can be performed any number of times.
For example, if , the array is , and Mocha selects the interval , then the new array is $[a_1,a_2\,\&\, a_5, a_3\,\&\, a_4, a_4\,\&\, a_3, a_5\,\&\, a_2]$.
Now Mocha wants to minimize the maximum value in the sequence. As her best friend, can you help her to get the answer?
Input
Each test contains multiple test cases.
The first line contains a single integer () — the number of test cases. Each test case consists of two lines.
The first line of each test case contains a single integer () — the length of the sequence.
The second line of each test case contains integers ().
Output
For each test case, print one integer — the minimal value of the maximum value in the sequence.
Note
In the first test case, Mocha can choose the interval , then the sequence becomes , where the first element is , and the second element is .
In the second test case, Mocha can choose the interval , then the sequence becomes , where the first element is , the second element is , and the third element is .
Samples
4
2
1 2
3
1 1 3
4
3 11 3 7
5
11 7 15 3 7
0
1
3
3
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 |