There are $N$ children standing in a line from left to right. The activeness of the $i$-th child from the left is $A_i$.
You can rearrange these children just one time in any order you like.
When a child who originally occupies the $x$-th position from the left in the line moves to the $y$-th position from the left, that child earns $A_x\times |x-y|$ happiness points.
Find the maximum total happiness points the children can earn.
输入格式
Input is given from Standard Input in the following format:
> $N$\
> $A_1 \quad A_2 \quad \cdots \quad A_N$
#### Constraints
- $2\le N\le 2000$
- $1\le A_i\le 10^9$
- All values in input are integers.
输出格式
Print the maximum total happiness points the children can earn.
样例输入 #1
4
1 3 4 2
样例输出 #1
20
样例输入 #2
6
5 5 6 1 1 1
样例输出 #2
58
样例输入 #3
6
8 6 9 1 2 1
样例输出 #3
85
提示
***For Sample #1:***
If we move the $1$-st child from the left to the $3$-rd position from the left, the $2$-nd child to the $4$-th position, the $3$-rd child to the $1$-st position, and the $4$-th child to the $2$-nd position, the children earns $1\times |1-3|+3\times |2-4|+4\times |3-1|+2\times |4-2|=20$ happiness points in total.