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Remove Duplicates

By FrontendAtlas Team · Updated Jan 31, 2026

Implement uniqueArray(arr) that removes duplicates while preserving order. Use a Set for O(n) time and clarify how to treat objects by reference, NaN, and mixed types so behavior is explicit and predictable. Concepts: arrays, sets, deduplication, iteration.

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Remove Duplicates: Implement uniqueArray(arr) that removes duplicates while preserving order. Use a Set for O(n) time and clarify how to treat objects by reference, NaN, and…. Expect arrays and sets decisions under easy level constraints.

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