Codeforces Round 738 (Div. 2)
A
Mocha and Math
Codeforces
900
原题
←B →
翻译中…

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.

翻译中…

This day, Mocha got a sequence $a$ of length $n$. In each operation, she can select an arbitrary interval $[l, r]$ and for all values $i$ ($0\leq i \leq r-l$), replace $a_{l+i}$ with $a_{l+i} \,\&\, a_{r-i}$ at the same time, where $\&$ denotes the bitwise AND operation. This operation can be performed any number of times.

翻译中…

For example, if $n=5$, the array is $[a_1,a_2,a_3,a_4,a_5]$, and Mocha selects the interval $[2,5]$, then the new array is $[a_1,a_2\,\&\, a_5, a_3\,\&\, a_4, a_4\,\&\, a_3, a_5\,\&\, a_2]$.

翻译中…

Now Mocha wants to minimize the maximum value in the sequence. As her best friend, can you help her to get the answer?

翻译中…

Input

翻译中…

Each test contains multiple test cases.

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The first line contains a single integer $t$ ($1 \le t \le 100$) — the number of test cases. Each test case consists of two lines.

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The first line of each test case contains a single integer $n$ ($1 \le n \le 100$) — the length of the sequence.

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The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ($0 \le a_i \le 10^9$).

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Output

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For each test case, print one integer — the minimal value of the maximum value in the sequence.

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Note

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In the first test case, Mocha can choose the interval $[1,2]$, then the sequence becomes $[ 0, 0]$, where the first element is $1\,\&\,2$, and the second element is $2\,\&\,1$.

翻译中…

In the second test case, Mocha can choose the interval $[1,3]$, then the sequence becomes $[ 1,1,1]$, where the first element is $1\,\&\,3$, the second element is $1\,\&\,1$, and the third element is $3\,\&\,1$.

翻译中…

样例

Input #1
4
2
1 2
3
1 1 3
4
3 11 3 7
5
11 7 15 3 7
Output #1
0
1
3
3
InputCopy OutputCopy
题目信息
题号
1559A
时间限制
1 s
内存限制
256 MB
标签
位运算
构造
数学

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。