#include <iostream>

#include <string>

#include <cstdlib>



using namespace std;



#include "Pair.h"



int main(int argc, char **argv) {

  Pair<std::string> ps;  // this usage instantiates a class Pair<std::string>

  std::string x("foo"), y("bar");

  

  ps.set_first(x);   // first_ = "foo", second_ = ""

  ps.set_second(y);  // first_ = "foo", second_ = "bar"

  ps.Swap();         // first_ = "bar", second_ = "foo"

  std::cout << ps << std::endl;  // nonmember overloaded operator<< invoked



  return EXIT_SUCCESS;

}