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

int main() {
    std::vector<int> gid = {4, 4, 5, 8, 1, 2, 3, 1, 42, 2, 42};

    std::sort(gid.begin(),gid.end());
    std::vector<int>::iterator itv(std::unique(gid.begin(),gid.end()));
    gid.erase(itv,gid.end());

    std::copy(gid.begin(),gid.end(), std::ostream_iterator<int>(std::cout, " "));
}