so use the reduce is optimial because O(n) ?

I just tried it and it worked.

Added that test.

Treating the whole array as a string is even better instead of iterating over it :)

Sorry but no. There is no minimum, it says he drinks that ammount and how to round. Not a kata issue.

Please use appropriate markdown formatting when posting code. See https://docs.codewars.com/training/troubleshooting#post-discourse.

There are errors in the tests for both "Test" and "Attempt" in javascript.

No, there are no errors in the tests. I recommend reading the description before attempting to solve the kata.