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answer: direct
beat: system-design
source: 1 article · updated: August 2, 2026
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Can a trie be built incrementally as new words are added to a system?

Yes. Insertion is O(p) per word. A trie is a mutable structure, not a static lookup table. If you're updating frequencies for ranking, track them alongside the trie and rebuild the top-k heaps incrementally; that's faster than full recomputation.

Answered in

Tries: Why Autocomplete Doesn't Scan Every Word

A trie finds all words with a prefix in O(p) time, independent of dictionary size. Radix compression and top-k heaps make autocomplete instant.

Crashtech Editorial August 2, 2026 System Design & Architecture

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