midTrie

Memory optimization: Array vs Hash Map in nodes

Updated Apr 28, 2026

Short answer

Arrays are O(1) but wasteful; Hash Maps are space-efficient but have O(1) average overhead.

Deep explanation

Mid-level analysis of Memory optimization: Array vs Hash Map in nodes. Focuses on algorithmic variations and efficiency trade-offs in real applications.

Real-world example

Search engine search bars.

Common mistakes

  • Searching for a prefix and returning the entire Trie instead of just child words.

Follow-up questions

  • How to limit autocomplete results?

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