Needs sample test cases for Python.

The default argument len should be length or l to avoid overwriting len().

I'll start working on some. Not sure I'll have them done any time soon.

Looks much simpler, but using eval() is a bit of a tradeoff.

Error in first Python Example Test. Input is stored in array, but should be called arr.

Python instructions are missing an example of required output.

Typo at end of description: "Retrun"

I didn't check how it was calculated before, but 1626 / 4 = 406.5. It looks right now.

Random test cases occassionally testing for February 29th in non-leap years (e.g. '16260229').

Random test cases are expecting incorrect responses.

For example:
Input: 19940106
Error: 'Thursday' should equal 'Wednesday'

1994-01-06 was a Thursday.

Thanks for all the feedback. It looks like most solutions here have this same process or use collections.Counter.

Is Counter much more efficient? For each item in collection, it has to check in the dict to see if it exists, then increment it. Is that also O(n^2)?

Thanks. I like that it doesn't require importing. I think superrafek's response is a bit more understandable than mine.

Starting code had method name covex_method but sample and final tests require hull_method. Starting function should be hull_method.

Looks good!

Is it hard to just remove the 0s? The function doesn't take 0 as an input anyway.