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Starter#Arrays#Polyfill
Array.prototype.flat Polyfill
Implement Array.prototype.flat from scratch with a configurable depth. Default depth is 1, not Infinity.
By modernDev2026-06-05Easy
flat flattens nested arrays up to a given depth. The interviewer check: do you default depth to 1 (not Infinity) and do you pass the depth counter through recursion correctly? flat(Infinity) should fully flatten any level of nesting.
Goal: Implement myFlat with correct default depth and recursive depth tracking.
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