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Implement Trie (Prefix Tree) is a medium coding interview question covering strings, trees, design — the kind asked at FAANG (Facebook/Meta, Apple, Amazon, Netflix, Google) and AI-first companies like Anthropic, OpenAI, and Nvidia.
Implement a Trie with: - insert(word): add a word, O(m) - search(word): return true if word exists, O(m) - starts_with(prefix): return true if any word starts with prefix, O(m)
Where m is the word/prefix length.
Used in autocomplete, spell checkers, IP routing (longest prefix match), and T9 predictive text.
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