#include <iostream>
#include <set>
#include <algorithm>

void
view (set < int >v)
{
  set < int >::iterator it;
  for (it = v.begin (); it != v.end (); it++) {
    cout << *it << " ";
  }
  cout << "\n";
}

main ()
{
  set < int >s;
  s.insert (7);
  s.insert (5);
  s.insert (6);
  view (s);
  set < int >::iterator it = s.find (7);
  cout << "Value: " << *it << "\n";
  cout << "Count: " << s.count (7) << "\n";
  cout << "Position: " << distance (s.begin (), it) << "\n";
  advance (it, -2);
  cout << "Before previous: " << *it << "\n";
  s.erase (7);
  view (s);
  s.erase (s.begin ());
  view (s);

  cout << "---\n";

  set < int >t, sum;
  t.insert (4);
  set_union (s.begin (), s.end (),
	     t.begin (), t.end (), inserter (sum, sum.begin ()));
  view (sum);
}