improve median

[RuSaG0]

Describe your change:

Fix a bug
In the last implementation, finding the median is not a pure function. It mutates the original array.

const arr = [3,2,1]
averageMedian(arr)
numbers = numbers.sort(sortNumbers)
so arr will be [1,2,3].

Why? The function for finding the median should not change arr by sorting

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Now this fn can work with generators and custom median selector (for example of str lengths)

[raklaptudirm]

Any iterables can be converted to an array by simply calling Array.from(iterator). I believe the previous implementation was more concise and to the point.

If you want a pure function, I would suggest a "rest" argument for the function.

[RuSaG0]

'I believe the previous implementation was more concise and to the point' - no problem
I returned the previous one, only now the passed array doesn't change

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updated