#include <map>
    #include <vector>
    #include <iostream>
    #include <algorithm>
    #include <iterator>
 
    using namespace std;
 
    std::vector<int> lonelyinteger(const std::vector<int>& a) 
    {
        std::vector<int> retValue;
        typedef std::map<int, int> IntMap;
        IntMap theMap;  
 
        // build the map
    	for_each(a.begin(), a.end(), [&](int n){ theMap[n]++; });
 
        // find all first entry with a count of 1
        for_each(theMap.begin(), theMap.end(),
           [&](const IntMap::value_type& pr)
                {if (pr.second == 1) retValue.push_back(pr.first); });
        return retValue;
    }
 
    int main()
    {
    	std::vector<int> TestVect = { 1, 1, 2, 3, 5, 0, 2, 8 };
    	std::vector<int> ans = lonelyinteger(TestVect);
        copy(ans.begin(), ans.end(), ostream_iterator<int>(cout," ")); 
    }
 
 

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