Finding and grouping anagrams by Python

Question

input: [\'abc\', \'cab\', \'cafe\', \'face\', \'goo\']
output: [[\'abc\', \'cab\'], [\'cafe\', \'face\'], [\'goo\']]

The problem is simple: it grou

Answer 1

The readable version:

from itertools import groupby
from operator import itemgetter

def norm(w):
  return "".join(sorted(w))

words = ['abc', 'cba', 'gaff', 'ffag', 'aaaa']

words_aug = sorted((norm(word), word) for word in words)

grouped = groupby(words_aug, itemgetter(0))

for _, group in grouped:
  print map(itemgetter(1), group)

The one-liner:

print list(list(anagrams for _, anagrams in group) for _, group in groupby(sorted(("".join(sorted(word)), word) for word in words), itemgetter(0)))

Prints:

[['aaaa'], ['abc', 'cba'], ['ffag', 'gaff']]