PV913STLArrayDiffer

#include <iostream>
#include <vector>
#include <algorithm>

template <class InIter>
InIter dedup(InIter begin, InIter end)
{
    InIter next{ begin };
    ++next;
    InIter out{ begin };

    while (begin != end)
    {
        if ((next != end) and (*begin != *next))
        {
            *out++ = *begin++;
            ++next;
        }
        else
        {
            std::advance(begin, 2);

            for (int cnt{ 0 }; next != end and cnt < 2; ++cnt, std::advance(next, 1));

        }
    }
    return out;
}

int main()
{
    std::vector<int> arrA{ 6,1,4,2,8,9,11,26,2,7,8,11,2,2,3 };
    std::vector<int> arrB{ 1,8,29,2,2,9,11,1,2,5,8,34,12,9,8 };

    std::sort(arrA.begin(), arrA.end());
    std::sort(arrB.begin(), arrB.end());

    std::copy(arrA.begin(), arrA.end(), std::ostream_iterator<int>(std::cout, " "));
    std::cout << '\n';
    std::copy(arrB.begin(), arrB.end(), std::ostream_iterator<int>(std::cout, " "));
    std::cout << '\n';

    std::cout << '\n';
    auto aUinque{ std::unique(arrA.begin(), arrA.end()) };
    auto bUinque{std::unique(arrB.begin(), arrB.end())};

    std::copy(arrA.begin(), aUinque, std::ostream_iterator<int>(std::cout, " "));
    std::cout << '\n';
    std::copy(arrB.begin(), bUinque, std::ostream_iterator<int>(std::cout, " "));
    std::cout << '\n';
    std::cout << '\n';

    std::vector<int> res;
    std::merge(arrA.begin(), aUinque, arrB.begin(), bUinque, std::inserter(res, res.begin()));
    std::copy(res.begin(), res.end(), std::ostream_iterator<int>(std::cout, " "));
    std::cout << '\n';
    std::cout << '\n';

    dedup(res.begin(), res.end());

    std::copy(res.begin(), res.end(), std::ostream_iterator<int>(std::cout, " "));
    std::cout << '\n';

    return 0;
}