Unique element

#include <iostream>
#include <string>
#include <sstream>
#include <vector>
#include <unordered_set>


using namespace std;


void unique_elements()
{
    int n;
    string st;
    unordered_multiset<int> u_set;
    vector<int> vec;
    stringstream ss;
    getline(cin, st);
    ss << st;
    while (ss >> n)
    {
        u_set.insert(n);
    }
    for (auto& it : u_set)
    {
        if (u_set.count(it) == 1)
        {
            vec.push_back(it);
        }
    }
    for (auto &it : vec)
    {
        cout << it << " ";
    }
}

int main()
{
    unique_elements();
    return 0;
}