• Solution checking does not treat output as a set


This problem's output validator does not treat its output as a set. My solution is

checkio = lambda first, second : ",".join(set(first.split(",")) & set(second.split(",")))

which yields

checkio("one,two,three", "four,five,one,two,six,three") => 'one,three,two'

on my local Python interpreter. However, on the web app, it returns some other permutation of the correct answer, yet it is marked as a failed test case.

From: http://www.checkio.org/mission/common-words/solve/


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