f1401.cpp

it is a usefull thing

//=====================================
// f1401.cpp
// define & using function template 
//=====================================
#include<iostream>
using namespace std;
template<typename T>
void swap(T& a, T& b){
  T temp=a; a=b; b=temp;
}//------------------------------------
int main(){
  double dx=3.5, dy=5.6;
  int ix=6, iy=7, ia=303, ib=505;
  string s1="good", s2="better";
  cout<<"double dx="<<dx<<",      dy="<<dy<<"\n";
  cout<<"int    ix="<<ix<<",        iy="<<iy<<"\n";
  cout<<"string s1=\""<<s1<<"\",   s2=\""<<s2<<"\"\n";
  swap(dx, dy);
  swap(ix, iy);
  swap(s1, s2);
  swap(ia, ib);
  cout<<"\nafter swap:\n";
  cout<<"double dx="<<dx<<",      dy="<<dy<<"\n";
  cout<<"int    ix="<<ix<<",        iy="<<iy<<"\n";
  cout<<"string s1=\""<<s1<<"\", s2=\""<<s2<<"\"\n";
}//====================================