///////////////////////////////////////////////////////////////////
// convert.cpp - Solution of MT#4-Q4                             //
//                                                               //
// This is a demo showing how to add two numbers very slowely.   //
///////////////////////////////////////////////////////////////////

#include <string>
#include <iostream>
#include <sstream>

typedef std::string str;

template <typename T>
T value(const str& s)
{
  std::istringstream cvt(s);
  T t;
  cvt >> t;
  return t;
}

template <typename T>
str ToString(const T& t)
{
  std::ostringstream cvt;
  cvt << t;
  return cvt.str();
}

template <typename T>
str sum(str larg, str rarg)
{
  return ToString((value<T>(larg) + value<T>(rarg)));
}

int main()
{
  std::cout << "\n  " << value<double>("3.1415927") << "\n\n";
  str arg1 = "1.234", arg2 = "4.321";
  std::cout << "\n  sum of " << arg1 << " and " << arg2 << " is " 
            << sum<double>(arg1,arg2) << "\n\n";
  std::cout << "\n  sum of " << arg1 << " and " << arg2 << " is " 
            << sum<int>(arg1,arg2) << "\n\n";  
  return 0;
}