# Revision history [back]

A better data structure than lists to make intersectoins is set, so you can first transform your list of lists into a list of sets:

sage: Lset = [set(l) for l in L]
sage: Lset
[{'B', 'C', 'D', 'E'},
{'A', 'C', 'D'},
{'A', 'B', 'D', 'E'},
{'A', 'B', 'C', 'D'}]


sage: s = Lset.pop()

Now you can intersect s with the remaining sets in Lset:
sage: s.intersection(*Lset)