#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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