lab_stl.h

#include <vector>

/* Complete the function so that it calculates the sum of the 
    unique values in the given sequence.
    i.e. if the sequence was 1, 2, 3, 2, 4, 2
    then the unique values would be 1, 2, 3, 4
    the sum of these unique values would be 10 

    Make use of the EXISTING features of the STL, it is possible
    to solve this entirely using existing functions. 
    
    The algorithms library in particular may be helpful
    https://en.cppreference.com/w/cpp/algorithm
*/

int sum_uniques( std::vector<int>::iterator begin, 
                 std::vector<int>::iterator end )
{
}