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

struct Thing
{
    int data;

    Thing() { data = 47; }
    Thing( int n ) { data = n; }
};

bool operator<( const Thing& a, const Thing& b )
{
    return a.data < b.data;
}

bool operator==( const Thing& a, const Thing& b )
{
    return a.data == b.data;
}


int main()
{
    set<Thing>  mySet;

    Thing t1, t2(49);

    mySet.insert( t1 );
    mySet.insert( t2 );

    set<Thing>::iterator it = mySet.begin();
    while( it != mySet.end() )
    {
        cout << (*it).data << endl;
        ++it;
    }

    return 0;
}