题目描述
You are given an array $a$ of $n$ integers. You are allowed to perform the following operation on it as many times as you want (0 or more times):
- Choose $2$ indices $i$,$j$ where $1 \le i < j \le n$ and replace $a_k$ for all $i \leq k \leq j$ with $|a_i - a_j|$
Print the maximum sum of all the elements of the final array that you can obtain in such a way.
Input
The first line contains a single integer $t$ ($1 \le t \le 10^5$) — the number of test cases.
The first line of each test case contains a single integer $n$ ($2 \le n \le 2 \cdot 10^5$) — the length of the array $a$.
The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ($1 \le a_i \le 10^9$) — the elements of array $a$.
It's guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.
Output
For each test case, print the sum of the final array.
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分
样例输入
样例输出
提示
In the first test case, it is not possible to achieve a sum $> 3$ by using these operations, therefore the maximum sum is $3$.
In the second test case, it can be shown that the maximum sum achievable is $16$. By using operation $(1,2)$ we transform the array from $[9,1]$ into $[8,8]$, thus the sum of the final array is $16$.
In the third test case, it can be shown that it is not possible to achieve a sum $> 18$ by using these operations, therefore the maximum sum is $18$.