List intersection
Returns a list of elements that exist in both lists.
- Create a
set
froma
andb
. - Use the built-in set operator
&
to only keep values contained in both sets, then transform theset
back into alist
.
def intersection(a, b): _a, _b = set(a), set(b) return list(_a & _b) intersection([1, 2, 3], [4, 3, 2]) # [2, 3]