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Problem - Search Autocomplete - Tries | Data Structures | Repovive

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Data Structures19 sections · 729 units49h total

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Problem - Search Autocomplete

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Design a search autocomplete system. For each character you type, return the top 3 historical sentences that have the prefix.

Sentences are ranked by frequency (times searched). If frequencies are equal, use lexicographic order.

Example:

input("i") → ["i love you", "island", "i love coding"]
input(" ") → ["i love you", "i love coding"]
input("a") → ["i a"]
input("#") → [] (# means end of input)

You're building a realistic autocomplete problem combining tries with frequency counting.

Constraints: up to 100 historical sentences, each with length up to 100.