#include <iostream>

template <class T, class U> void varSwap(T& a, U& b) {
  T t;
  t = a;
  a = b;
  b = (U) t;
}

int main(int argc, char** argv) {
  using namespace std;
  double a = 1.1;
  double b = 2.2;
  varSwap(a,b);
  cout << a << "," << b << endl;
  int c = 1;
  int d = 2;
  varSwap(c,d);
  cout << c << "," << d << endl;
  long e = 3;
  int f = 4;
  varSwap(e,f);
  cout << e << "," << f << endl;
}