Codeforces Round 877 (Div. 2)
A
Blackboard List
Codeforces
800
原题
←B →
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Two integers were written on a blackboard. After that, the following step was carried out $n-2$ times:

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  • Select any two integers on the board, and write the absolute value of their difference on the board.
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After this process was complete, the list of $n$ integers was shuffled. You are given the final list. Recover one of the initial two numbers. You do not need to recover the other one.

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You are guaranteed that the input can be generated using the above process.

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Input

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The first line of the input contains a single integer $t$ ($1 \le t \le 100$) — the number of test cases. The description of the test cases follows.

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The first line of each test case contains a single integer $n$ ($3 \le n \le 100$) — the size of the final list.

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The next line of each test case contains $n$ integers $a_1, a_2, \ldots a_n$ ($-10^9 \le a_i \le 10^9$) — the shuffled list of numbers written on the blackboard.

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It is guaranteed that the input was generated using the process described above.

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Output

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For each test case, output a single integer $x$ — one of the two initial numbers on the blackboard.

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If there are multiple solutions, print any of them.

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Note

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For the first test case, $a$ can be produced by starting with either $9$ and $2$, and then writing down $|9-2|=7$, or starting with $9$ and $7$ and writing down $|9-7|=2$. So $2$, $7$, and $9$ are all valid answers, because they all appear in at least one valid pair.

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For the second test case, we can show that the two initial numbers must have been $-4$ and $11$.

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For the fourth test case, the starting numbers could have been either $3$ and $3$, or $3$ and $0$, so $3$ and $0$ are both valid answers.

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For the fifth test case, we can show that the starting numbers were $8$ and $16$.

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样例

Input #1
9
3
9 2 7
3
15 -4 11
4
-9 1 11 -10
5
3 0 0 0 3
7
8 16 8 0 8 16 8
4
0 0 0 0
10
27 1 24 28 2 -1 26 25 28 27
6
600000000 800000000 0 -200000000 1000000000 800000000
3
0 -1000000000 1000000000
Output #1
9
11
-9
3
8
0
-1
600000000
0
InputCopy OutputCopy
题目信息
题号
1838A
时间限制
1 s
内存限制
256 MB
标签
构造
数学

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