Конструктор и деструктор для cout

int main()
{
    cout << "Hello" << " " << "World!";
}

int main()
{
    cout << "Hello" << " " << "World!";
    cout << 42;
}

#include <iostream>
 
 
struct cout_tag {} cout;
 
 
struct cout_impl_t {
   cout_impl_t()  {
      std::cout << ">>>" << std::endl;
   }
   cout_impl_t(cout_impl_t const&) {
      ++counter;
   }
   ~cout_impl_t() {
      if (counter == 0) {
         std::cout << "<<<" << std::endl;
      } else {
         --counter;
      }
   }
   
private:
   static std::size_t counter;
};
 
std::size_t cout_impl_t::counter(0);
 
 
typedef std::ios_base & (*ios_base_manipulator_t)(std::ios_base &);
typedef std::ostream &  (*ostream_manipulator_t )(std::ostream & );
 
 
template<typename Type>
cout_impl_t operator <<(cout_impl_t impl, Type const& type) {
   std::cout << type;
   return impl;
}
 
cout_impl_t operator <<(cout_impl_t impl, ostream_manipulator_t manipulator) {
   std::cout << manipulator;
   return impl;
}
 
cout_impl_t operator <<(cout_impl_t impl, ios_base_manipulator_t manipulator) {
   std::cout << manipulator;
   return impl;
}
 
template<typename C, typename T>
cout_impl_t operator <<(cout_impl_t impl, std::basic_ios<C, T> & (*manipulator)(std::basic_ios<C, T> &)) {
   std::cout << manipulator;
   return impl;
}
 
 
template<typename Type>
cout_impl_t operator <<(cout_tag, Type const& type) {
   return (cout_impl_t() << type);
}
 
cout_impl_t operator <<(cout_tag, ostream_manipulator_t manipulator) {
   return (cout_impl_t() << manipulator);
}
 
cout_impl_t operator <<(cout_tag, ios_base_manipulator_t manipulator) {
   return (cout_impl_t() << manipulator);
}
 
template<typename C, typename T>
cout_impl_t operator <<(cout_tag, std::basic_ios<C, T> & (*manipulator)(std::basic_ios<C, T> &)) {
   return (cout_impl_t() << manipulator);
}
 
 
int main()
{
    cout << "Hello" << " " << "World!" << std::endl;
    cout << 42 << std::endl;
}