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Remove Duplicates from Array

JavaScript
easy

Given an array, your task is to return a new array with all duplicate elements removed.
You should preserve the order of the first occurrence of each element.

Input

  • An array of any primitive values: number, string, boolean, null, or undefined.

Output

  • A new array containing only unique elements, in the order they first appear.

Edge Cases

  • Empty array should return an empty array.

  • Duplicates can be of different types (e.g., 1 and "1" are not the same).

  • Object and array references are considered unique even if they look identical.

Examples

removeDuplicates([1, 2, 2, 3, 4, 4]); // Output: [1, 2, 3, 4] removeDuplicates(["a", "b", "a", "c"]); // Output: ["a", "b", "c"] removeDuplicates([1, "1", 1]); // Output: [1, "1"] removeDuplicates([]); // Output: [] removeDuplicates([true, false, true]); // Output: [true, false]

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