#include <iostream>

using namespace std;

template <class T> class DataWrapper;
template <class T> ostream& operator << (ostream& out, const DataWrapper<T>& d);

template <class T>
class DataWrapper{
private:
    T data;
public:
    friend ostream& operator << <T>(ostream& out, const DataWrapper<T>& d);
};

template <class T>
ostream& operator << (ostream& out, const DataWrapper<T>& d){
    return out << d.data;
}

template <class T>
DataWrapper<T>::DataWrapper(T d) : data(d){}

int main(){
    DataWrapper<int> intWrapper(5);
    DataWrapper<char> charWrapper('a');
    DataWrapper<string> stringWrapper("Hello!");

    cout << intWrapper << endl;
    cout << charWrapper << endl;
    cout << stringWrapper << endl;
}