------Description-----
This task requires writing a Lean 4 method that given a 0-indexed integer array `nums` representing the scores of students in an exam. A teacher wants to select a non empty group of students such that the strength of group is maximized. 

The strength of a group is defined as the product of the selected student scores.

You can choose any non-empty subset of students. The goal is to compute the maximum product of any such subset. 


----Input---
nums: An non-empty list of integers.

-----Output-----

An integer representing the maximum strength.

