How does a trie handle autocomplete with typos or fuzzy matching?
A pure trie handles exact-prefix matches only. Fuzzy matching (e.g., Levenshtein distance) requires either a separate inverted index over all words or a specialized data structure like a BK-tree. Most production systems use a trie for speed, then re-rank fuzzy/typo results in a second pass.
Answered in
Tries: Why Autocomplete Doesn't Scan Every WordA trie finds all words with a prefix in O(p) time, independent of dictionary size. Radix compression and top-k heaps make autocomplete instant.
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