python - Get indices of the top N values of a list

Question

I have a list say a = [5,3,1,4,10]. I need to get indices of the top two values of the list, that is for 5 and 10 I would get [0, 4]. Is there a one-liner that Python offers for such a case?

Answer 1

sorted(range(len(a)), key=lambda i: a[i])[-2:]

or

sorted(range(len(a)), key=lambda i: a[i], reverse=True)[:2]

or

import operator

zip(*sorted(enumerate(a), key=operator.itemgetter(1)))[0][-2:]

or (for long lists), consider using heapq.nlargest

zip(*heapq.nlargest(2, enumerate(a), key=operator.itemgetter(1)))[0]