Getting the key to the maximum component of a tuple in a dictionary of tuples

Question

I have a dictionary whose components are all 2-tuples (all integers) and I want to find the key to the tuple with the largest second component. How can I do this in Python 2.6?

Answer 1

The following will do it (where d is your dictionary):

max(d.items(), key=lambda(k,v):v[1])[0]

In this solution, the key (if you pardon the pun) is to use the optional key argument to max .

Answer 2

aix' answer is a good one. You can achieve the same without using lambdas if you prefer, though:

import operator
m = max(d.iteritems(), key=operator.itemgetter(1))[0]