LeetCode 49 Group Anagrams - Why Naive Fails

You might compare every pair of strings to check if they're anagrams. For each pair, you'd compare character counts in $O(k)$ time where $k$ is string length.

With $n$ strings, that's $O(n^2)$ pairs. Total: $O(n^2 \cdot k)$.

For $n = 10^4$ strings of length $100$, that's roughly $10^{10}$ operations. Way too slow.

You need a way to identify anagrams without comparing every pair directly.