concatenation of an int to a string coerces to a string

Can someone explain why this would work?
didnt they want the answer in string format?

agree, haven't taken the complexity into consideration while solving the task

sorting the array is wasteful time for this task.
we need to calculate only the difference between max and min values.
finding max and min can be done in O(n) while sorting array with
sort will take in worst case nlogn

Readble but unnecessary overhead.
Can be done with simple loop.