Got an email for the Online Assessment. 5 questions were asked. 2 were multiple-choice, and the other 3 were based on DSA concepts coding.

Their standard was high, considering the difficulty level.

The BytePlus platform has n servers, where the data stored on the i-th server is represented by the array memory. To manage the servers efficiently, you can perform the following operation any (possibly zero) number of times:

• Choose an index idx, such that 1 ≤ idx ≤ n/2.
• Swap the data of the pair of servers that are equidistant from the beginning and the end of the array memory and have a distance less than or equal to idx.

The total working efficiency of the servers is calculated as the sum of the product of the data present in each server with the index of that server.

Given an integer n and an array memory, find the maximum possible total working efficiency that we can get. Since the total working efficiency can be very large, print it modulo 10^9 + 7.