//  A1_5.cpp

#pragma warning(disable : 4786)
#include <iostream>
#include <string>
#include <set>
using namespace std;

template <class T> set<T> getChars(const string &s) {

  set<T> cs;
  int i;
  for(i=0; i<s.size(); i++)
    cs.insert(s[i]);
  return cs;
}

void main() {

  cout << "\n  ";
  set<char> cs = getChars<char>("this is a string");  
                 // explicit instantiation, <char>, is necessary
  set<char>::iterator it;
  for(it=cs.begin(); it!=cs.end(); it++)
    cout << *it;
  cout << "\n\n";
}