Maximum score

You are given an array $A$ of size $N.$ You have to return the maximum possible score after applying the below operations floor $(\frac{N}{2})$ times.

An operation on array $A$ is:

Select any two elements $x$ and ${?}^{A}Y$ array A and add $\frac{?}{x}-\frac{Y}{?}$ to your score.

Delete $x$ and $Y$ from array $A.$

Task

Print the maximum possible score.

Notes

$flr(x)$ is the largest integer that is smaller than or equal to $x.$

$|x|$ is the absolute value of $x.$write in python