C++ code to delete duplicates from an array using a heap structure to achieve O(n*log n) performance

deleteDuplicates.cpp

#include <cstdlib>
#include <algorithm>
// Delete duplicate entries from an array using C++ heap.
int *deleteDuplicates(int theArray[], size_t theArrayLength)
{
    int *topSortedArray = theArray + theArrayLength;

    if (theArrayLength > 1)
    {
        // Heap is in theArray[0:heapEnd-1]
        size_t heapEnd = theArrayLength;
        std::make_heap(theArray, theArray+heapEnd);

        // Pop the first element, which is the max element
        int prevElement = theArray[0];
        std::pop_heap(theArray, theArray+heapEnd);
        --heapEnd;

        // push the max element onto the sorted area
        --topSortedArray;
        *topSortedArray = prevElement;

        while (heapEnd > 0)
        {
            int currentElement = theArray[0];
            std::pop_heap(theArray, theArray+heapEnd);
            --heapEnd;

            if (currentElement != prevElement)
            {
                --topSortedArray;
                *topSortedArray = currentElement;
                prevElement = currentElement;
            }
        }
    }

    return topSortedArray;
}

Delete duplicate entries in an array using C++ heap