Cirno has a sequence $a$ of length $n$. She can perform either of the following two operations for any (possibly, zero) times unless the current length of $a$ is $1$:
- Reverse the sequence. Formally,
$[a_1,a_2,\ldots,a_n]$becomes$[a_n,a_{n-1},\ldots,a_1]$after the operation. - Replace the sequence with its difference sequence. Formally,
$[a_1,a_2,\ldots,a_n]$becomes$[a_2-a_1,a_3-a_2,\ldots,a_n-a_{n-1}]$after the operation.
Find the maximum possible sum of elements of $a$ after all operations.
Input
The first line of input contains a single integer $t$ ($1 \leq t \leq 100$) — the number of input test cases.
The first line of each test case contains a single integer $n$ ($1\le n\le 50$) — the length of sequence $a$.
The second line of each test case contains $n$ integers $a_1,a_2,\ldots,a_n$ ($|a_i|\le 1000$) — the sequence $a$.
Output
For each test case, print an integer representing the maximum possible sum.
Note
In the first test case, Cirno can not perform any operation, so the answer is $-1000$.
In the second test case, Cirno firstly reverses the sequence, then replaces the sequence with its difference sequence: $[5,-3]\to[-3,5]\to[8]$. It can be proven that this maximizes the sum, so the answer is $8$.
In the third test case, Cirno can choose not to operate, so the answer is $1001$.
样例
5
1
-1000
2
5 -3
2
1000 1
9
9 7 9 -9 9 -8 7 -8 9
11
678 201 340 444 453 922 128 987 127 752 0
-1000
8
1001
2056
269891
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