Remove Duplicates from Sorted

Arrays & Two-Pointersmedium

Course · Section 11: Working With Arrays · Lecture 149: Simple Array Methods

Implement `removeDuplicatesSorted(arr)` returning the unique values from a sorted array, in order.

Input: removeDuplicatesSorted([1,1,2,3,3])

Output: [1,2,3]

Input: removeDuplicatesSorted([1])

Output: [1]

+ 1 hidden test run on Submit.

Common pitfalls

Using a Set works but ignores the sorted property; comparing neighbors is O(1) space beyond output.

Approach & explanation (try first)

Because duplicates are adjacent in sorted input, comparing each value to the last kept one removes them in one pass.

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