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$ curl repovive.com/roadmaps/pattern-22/hash-map-patterns/group-anagrams-implementation

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$ curl repovive.com/roadmaps/pattern-22/hash-map-patterns/group-anagrams-implementation

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LeetCode 49 Group Anagrams - Implementation - Hash Map Patterns | Pattern 22: LeetCode Interview Patterns | Repovive

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Pattern 22: LeetCode Interview Patterns24 sections · 736 units32h total

Open in Course

LeetCode 49 Group Anagrams - Implementation

The approach

Use sorted characters as the key. All anagrams share the same sorted form. Group strings by their sorted key.

Here's the solution:

function groupAnagrams(strs):
    groups = {}
    for s in strs:
        key = tuple(sorted(s))
        if key not in groups:
            groups[key] = []
        groups[key].append(s)
    return list(groups.values())

$O(n \cdot k \log k)$ time, $O(n \cdot k)$ space where $k$ is max string length.