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Starter#Objects#Drills
JS Object Transformations Drill
Practice the object transformation patterns interviewers love — group by, flatten, invert, pick, omit, deep merge, and more. 15 quick drills with instant feedback.
By modernDev2026-03-20
A focused drill set covering the most common object transformation patterns in JavaScript interviews. Write a solve(input) function for each problem and get instant pass/fail feedback. Covers Object.fromEntries, Object.entries, reduce, recursion, and more.
Goal: Complete all 15 object transformation drills. Aim to solve each without hints!
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