[Solution] Swap and Take Codeforces Solution

E. Swap and Take

time limit per test

2 seconds

memory limit per test

1024 megabytes

input

standard input

output

standard output

You're given an array consisting of 𝑛$n$ integers. You have to perform 𝑛$n$ turns.

Initially your score is 0$0$.

On the 𝑖$i$-th turn, you are allowed to leave the array as it is or swap any one pair of 2$2$ adjacent elements in the array and change exactly one of them to 0$0$(and leave the value of other element unchanged) after swapping. In either case(whether you swap or not), after this you add 𝑎𝑖$a_i$ to your score.

What's the maximum possible score you can get?

Input

The first line contains a single integer 𝑛$n$ (2≤𝑛≤500$2\le n\le 500$).

The second line contains 𝑛$n$ integers 𝑎1,𝑎2,…,𝑎𝑛$a_1,a_2,\dots ,a_n$ (1≤𝑎𝑖≤106$1\le a_i\le {10}^6$).

Output

Print a single integer — the maximum possible score.

Note

In the first example, to get the maximum score we do as follows. Do nothing on the first turn, add 3$3$ to the score. Swap the first and the second elements and turn 1$1$ to 0$0$ on the second turn, and add 3$3$ to the score. The final score is 6$6$

$\mathrm{<br>}$