This problem follows the Hash Map Grouping pattern, commonly found in the Arrays & Hashing category. Recognizing this pattern is key to solving it efficiently in an interview setting.
Sort each string and use as key. Group by sorted key in a hash map.
Anagrams produce the same string when sorted — use sorted characters as the hash map key to group them automatically.
groups = defaultdict(list)
for s in strs:
key = ''.join(sorted(s))
groups[key].append(s)
return list(groups.values())Practice Group Anagrams and similar Arrays & Hashing problems with flashcards. Build pattern recognition through active recall.
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