Question

I have a list which contains 1-5 lists within it. I want to return only the values which appear in all the lists. I can easily create an exception for it there is only one list, but I can’t think of a way round it when there are an multiple (unknown number of) lists. For example:

[[1,2,3,4],[2,3,7,8],[2,3,6,9],[1,2,5,7]]

would only return 2, because it’s the only list item to appear in all the sub-lists

How can I achieve this?

Answer 1

reduce(set.intersection, (set(x) for x in [[1,2,3,4],[2,3,7,8],[2,3,6,9],[1,2,5,7]]))