#include <algorithm>
#include <set>
#include <iostream>
using namespace std;

 int main()
 {

   //Initialize some sets
   int a1[10] = {1,2,3,4,5,6,7,8,9,10};
   int a2[6]  = {2,4,6,8,10,12};

   set<int> s1(a1, a1+10), s2(a2, a2+6),answer ;
   cout << "s1=";
   copy(s1.begin(), s1.end(),
        ostream_iterator<int>(cout," "));
   cout << "\ns2=";
   copy(s2.begin(), s2.end(),
        ostream_iterator<int>(cout," "));

   //Demonstrate set_difference
   set_difference(s1.begin(), s1.end(),
                  s2.begin(), s2.end(), inserter(answer,answer.begin()));
   cout << "\nThe set-difference of s1 and s2 =";
   copy(answer.begin(), answer.end(),
        ostream_iterator<int>(cout," "));
   cout << endl;
   return 0;
 }