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Citadel Interview Question

CitadelQuantitative Researcher Interview

Algorithm: given an array of numbers: 1,5,3,2,4,2,3,1,2,3,2,4. Return another array with duplicate numbers in consecutive positions and in order of their first appearance, in the example the result should be: 1,1,5,3,3,3,2,2,2,2,4,4

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