7 Constructor

#include <iostream>
using namespace std;
class student{
    int x;
    public:
    student(){ // default
        x = 67;
    }
    student(int a){ // parameterized
        x = a;
    }
    student(student & a){ // copy
        x = a.x;
    }

    void display(){
        cout<<x<<endl;
    }
};
int main()
{
    student s1;     // defalut
    student s2(40); // parameterized
    student s3(s2); // copy
    s1.display();
    s2.display();
    s3.display();
    return 0;
}
/*
Output
67
40
40
*/