#include <iostream>
#include <set>
#include <vector>
#include <algorithm>
#include <iterator>
using std::set;
using std::vector;
using std::set_symmetric_difference;
using std::ostream_iterator;
using std::cout;
int main()
{
vector<int> first={1,1,2,3,7};
vector<int> second={1,2,5,6,7};
const set<int> alpha(begin(first),end(first));
const set<int> beta(begin(second),end(second));
ostream_iterator<int> out(cout,", ");
set_symmetric_difference(begin(alpha),end(alpha),begin(beta),end(beta),out);
return 0;
}
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