59defaultpintemp.cpp

#include <iostream>
#include <cstring>
#include <fstream>
using namespace std;

// DEFAULT PARAMETERS IN TEMPLATE
template <class T1 = int, class T2 = float, class T3 = char> // Here, we passed the value of custom datatype T in the template
class Happy
{
    T1 datax;
    T2 datay;
    T3 dataz;

public:
    Happy(T1 a, T2 b, T3 c)
    {
        datax = a;
        datay = b;
        dataz = c;
    }
    void display()
    {
        cout << "Data of class is : " << this->datax << ", " << this->datay << ", " << this->dataz << endl;
    }
};
int main()
{
    Happy<> obj(2, 6.5, 'l'); // to access the default values of template, keep the <> empty
    obj.display();

    Happy<char, char, int> OBJ('F', 'r', 99); // if you provide different parameters in object declaration, they will take over
    OBJ.display();
    return 0;
}