Day 2EasyHackerRank

Sparse Arrays

Hash Table, Frequency Counter

Problem

💡 Problem Statement

Given a collection of input strings and a collection of query strings, for each query string, determine how many times it occurs in the list of input strings. Return an array of the results.

Solve it yourself before you look

Reading the solution first feels like progress, but it makes the next similar problem — and the interview version — much harder, because you skipped the part where you figure it out. Give it an honest 20–30 minutes. Stuck? Re-read the pattern, watch the concept video, or try the brute force first.

Hidden: approach · solution code

💡 Problem Statement

Solve it yourself before you look

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